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#51 Re: Help Me ! » Radicand Comes Out » 2023-11-20 12:35:39
KerimF wrote:May I add...
sqrt{(a + b)^2} = ±(a + b)
like sqrt{(1 + 2)^2} = sqrt(9) = ±3
amnkb wrote:[addressed to KerimF] actually, sqaure root is defined to be the positive answer
sologuitar wrote:Yeah, no kidding. Where is your math work? Seriously, I personally don't want to read a story about each problem posted. Just do the math. Get it?
what 'math' could i 'do' to correct the wrong info?
arent math definitions part of math?
but i'll leave bad info alone in future
sry
Also, stop saying sorry all the time. Understand? Just be normal, dude.
#52 Re: Help Me ! » Find Number of Weeks » 2023-11-20 12:34:23
sologuitar wrote:Joe and Steve are saving money. Joe starts with $105 and saves $5 per week. Steve starts with $5 and saves $15 per week. After how many weeks do they have the same amount of money?
Brother, if I ask for a hint or ask if my steps are OK so far, don't solve the problem unless I ask you to do so.
#53 Re: Help Me ! » Solve for c » 2023-11-20 12:33:05
sologuitar wrote:Solve 1/a = 1/b + 1/c
Thanks but I didn't ask you to solve for c.
I often find myself going through a textbook like walking in the park on a sunny day. I then reach a certain chapter or section that requires knowledge of all the previous math material I have learned or thought I learned. Confusion sets in to create a stumbling block that keeps me wondering if I truly learned anything at all in my previous math courses or chapters or sections that I just completed. Why does this happen? How do I keep myself from forgetting the earlier chapters or sections in math textbooks?
#54 Re: Help Me ! » Solve for m » 2023-11-20 12:32:05
(y -b)/x = m is right.
m is the slope.
Thanks. I often find myself going through a textbook like walking in the park on a sunny day. I then reach a certain chapter or section that requires knowledge of all the previous math material I have learned or thought I learned. Confusion sets in to create a stumbling block that keeps me wondering if I truly learned anything at all in my previous math courses or chapters or sections that I just completed. Why does this happen? How do I keep myself from forgetting the earlier chapters or sections in math textbooks?
#55 Help Me ! » Probability of Red Section » 2023-11-19 11:29:20
- sologuitar
- Replies: 6
A map has 5 color sections. One of the sections is red. What is the probability of selecting the red section blindfolded?
P(red section) = one red/(5 colors)
P(red section) = 1/5
You say?
#56 Help Me ! » Solve for m » 2023-11-19 11:08:27
- sologuitar
- Replies: 4
y = mx + b
Subtract b from both sides.
y - b = mx + b - b
y - b = mx
Divide both sides by x.
(y - b)/x = m
You say?
#57 Help Me ! » Solve for F » 2023-11-19 11:06:04
- sologuitar
- Replies: 6
Solve C = (5/9)(F - 32) for F.
I think the first step is to multiply both sides by 9. This will remove the fraction.
9C = 9[(5/9)(F - 32)]
9C = 5(F - 32)
9C = 5F - 160
Is this OK so far?
#58 Help Me ! » Solve for c » 2023-11-19 10:41:28
- sologuitar
- Replies: 3
Solve 1/a = 1/b + 1/c
I think the first step is to multiply both sides of the equation by ABC.
(abc)(1/a) = (abc)(1/b + 1/c)
bc = ac + ab
Is this OK so far?
#59 Help Me ! » Find Number of Weeks » 2023-11-19 10:37:48
- sologuitar
- Replies: 2
Joe and Steve are saving money. Joe starts with $105 and saves $5 per week. Steve starts with $5 and saves $15 per week. After how many weeks do they have the same amount of money?
I think two equations are needed.
Let w = number of weeks
Joe's equation: y = 105 + 5w
Steve equation: y = 5 + 15w
Is this OK so far?
#60 Re: Help Me ! » Company's Profit or Loss » 2023-11-19 10:34:54
It's kind of the same thing
Kind of? It's either the same thing or it is not.
#61 Re: Help Me ! » Radicand Comes Out » 2023-11-19 10:33:40
amnkb wrote:KerimF wrote:May I add...
sqrt{(a + b)^2} = ±(a + b)
like sqrt{(1 + 2)^2} = sqrt(9) = ±3
actually, sqaure root is defined to be the positive answer
Based on this definition, you mentioned, you are totally right.
I just added what I know because in my designs, if I ended up with the equation:
x^2 - 9 = 0
X^2 = 9
x = sqrt(9) = ±3
I had to consider both results.But in case you believe that I do wrong, and I have to ignore always the negative result, please accept my apology.
No apology needed. Let's stay on the math course.
#62 Re: Help Me ! » Radicand Comes Out » 2023-11-18 04:02:28
KerimF wrote:May I add...
sqrt{(a + b)^2} = ±(a + b)
like sqrt{(1 + 2)^2} = sqrt(9) = ±3
actually, sqaure root is defined to be the positive answer
Yeah, no kidding. Where is your math work? Seriously, I personally don't want to read a story about each problem posted. Just do the math. Get it?
#63 Re: Help Me ! » Real Solutions of the Quadratic Equation...B » 2023-11-18 04:00:19
sologuitar wrote:When you say "a solution", do you mean there are more solutions?
As you know, in general, a quadratic equation has two roots (real or complex) if (b^2 - 4ac) ≠ 0. We may say that 'r' is one of them (for known a, b and c).
Much better this time. Less lectures and philosophy and more mathematics.
#64 Re: Help Me ! » Real Solutions of the Quadratic Equation...A » 2023-11-18 03:59:10
sologuitar wrote:How did you know what to do? What data in the application led you to work out the problem as you did?
As you know, to compare two solutions, one just needs to find each of them first.
But in the case of someone who didn't hear yet the solution (root’s formula) of a quadratic equation, the proof will be much longer.
For instance, I forgot the math trick by which the root’s formula was found (when I was at school about 60 years ago), so now I needed to search “How to find the quadratic equation formula” to remember it
Keep all your math tricks to yourself. Get involved in the conversation by providing your math work and less lectures.
#65 Re: Help Me ! » Tricky or Lengthy Word Problems » 2023-11-18 03:57:40
May I add...
Necessity is the mother of invention... or innovation.
In other words, even the most intelligent human won't solve a problem if he is not interested in doing it.Based on my own observations, I doubt a serious person cannot find a practical solution, directly or indirectly, of a project that he needed really in his personal life, though it may take him a day, a week, a month, a year, or even many decades to find it.
You are now a philosopher of mathematics, huh? Let's see more problem solving and less lectures.
#66 Re: Help Me ! » Square Root Raised to Square Root » 2023-11-18 03:54:58
May I add...
The main difficulty in solving a practical problem is to find the formulas/equations which will lead, usually by using math tricks, to the end values to be applied for a certain project.
We are fortunate now that, for solving an equation or formula, there are many numerical tools (likely PC programs), to choose from, which help us find the numerical answer(s) we are looking for.
For instance, solving a new problem whose formulas/equations are not known yet by humans, even the most intelligent robot cannot do it. Otherwise, humans will be no more needed in research departments
Everything you stated I already know.
#67 Re: Help Me ! » Border of Circular Swimming Pool » 2023-11-17 06:57:30
sologuitar wrote:A circular pool measures 10 feet across. One cubic yard of concrete is to be used to create a circular border of uniform width around the pool. If the border is to have a depth of 3 inches, how wide will the border be?
forbuytoo wrote:looking forward to seeing the answer.
Wow! Nicely-done! I like your step by step process to reach the answer.
#68 Re: Help Me ! » Find Value of k » 2023-11-17 06:55:23
sologuitar wrote:Find k such that the equation kx^2 + x + k = 0.
Just answer the questions posted and keep your text math-related.
bob- heres the rest of the question-->
solo- sorry
You got it right. Thank you.
#69 Re: Help Me ! » Find Value of k » 2023-11-16 18:28:55
Bob wrote:hi amnkb
Yes, I did that too. But it doesn't tell what k is. There must be more to this question
i agree
The question has been presented as found in the textbook. I don't think I'm wrong about using the discriminant to find k.
#70 Re: Help Me ! » Find Value of k » 2023-11-16 18:26:55
sologuitar wrote:Find k such that the equation kx^2 + x + k = 0.
Just answer the questions posted and keep your text math-related.
This does not lead to the value of k. I think the discriminant is needed here to find k. What else can it be?
#71 Re: Help Me ! » Real Solutions of the Quadratic Equation...B » 2023-11-16 18:24:27
sologuitar wrote:Show that the real solutions of the equation ax^2 + bx + c = 0 are the reciprocals of the real solutions of the equation cx^2 + bx + a = 0. Assume that b^2 - 4ac is greater than or equal to 0.
Just answer the questions posted and keep your text math-related.
Again, what data in the application led you to work out the problem as you did? You said (1/r) is a solution to the quadratic equation given. When you say "a solution", do you mean there are more solutions?
#72 Re: Help Me ! » Real Solutions of the Quadratic Equation...B » 2023-11-16 18:21:37
I've written down the solutions using the quadratic formula, let's say x and x' for the first and y and y' for the second.
To be reciprocals x times y (or maybe y') must equal 1 and similarly x' with y' or y
Haven't tried it yet but I think it should work.
edit: tried it now. It does if you do x times y' (in other words take the plus root for one with the minus root of the other ... then loads of canceling, leaving 4ac/4ac = 1).
Bob
The wording in this application is horrible.
#73 Re: Help Me ! » Real Solutions of the Quadratic Equation...A » 2023-11-16 18:20:00
sologuitar wrote:Show that the real solutions of the equation ax^2 + bx + c = 0 are the negatives of the real solutions of the equation ax^2 - bx + c = 0. Assume that b^2 - 4ac is greater than or equal to 0.
Just answer the questions posted and keep your text math-related.
How did you know what to do? What data in the application led you to work out the problem as you did?
#74 Re: Help Me ! » Comparing Television Screen Size » 2023-11-16 18:17:53
sologuitar wrote:The screen size of a TV is determined by the length of the diagonal of the rectangular screen. Traditional TVs come in a 4 : 3 format, meaning the ratio of the length to the width of the rectangular screen is 4 yo 3.
A. What is the area of a 37-inch traditional TV screen?
B. What is the area of a 37-inch LCD TV whose screen is in a 16 : 9 format. Which screen is bigger?
Just answer the questions posted and keep your text math-related.
part A
part B
Glad to know I got the right equation for both TV set models.
#75 Re: Help Me ! » Find Width of Border » 2023-11-16 18:16:21
sologuitar wrote:A lanscaper, who just completed a rectangular flower garden measuring 6 feet by 10 feet, orders 1 cubic yard of premixed cement, all of which is to be used to create a border of uniform width around the garden. If the border is to have a depth 3 inches, how wide will the border be?
Just answer the questions posted and keep your text math-related.
How did you get the area of the border and volume of cement expressions?