Math Is Fun Forum

SlowlyFading

Member

Registered: 2012-06-12

Posts: 149

I Need Help With a Few Algebra Questions!

Okay, so I've already done these questions a couple times and my teacher keeps telling me they're wrong without really telling me what I need to fix, just telling me where I messed up, the problem is I don't know how to do these problems correctly. So I'm coming here now!

The questions:
2. Slope equals 2 and the line goes through the point (-1, 3)
y + k = m(x - h)

(So for that one they just want you to get h and k and put 2 for the slope. I don't know how you find h and k with -1 and 3.)

5. The line goes through the points (1/2, 3/2) and (-1/4, 5/4)

(You have to do the same thing on this one, they just don't give you a slope.)

12. Find the slope-intercept form of the equation that goes through these two points.

(The two points are 1,115.00 and 2,83.00.)

So, I need somebody to give me the answers to those three problems and explain to me how they got the answer, because I want to understand how to do these problems, not just get the answer.

Thank you!

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I'm just here to get some help with an online math course I'm taking.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: I Need Help With a Few Algebra Questions!

Hi SlowlyFading;

For 2) you only need y = mx +b. Where m is the slope and b is the y intercept.

b = 5

The equation of the line is y = 2x+5

For 5) use the formula

where (x1,y1) and (x2,y2) are the points. You just have to substitute to get:

For 12) you can use the same formula as in 5) or you can use y = mx+b for both sets of points and solve a simultaneous set of linear equations.

m = -32 and b = 147

The equation is y = -32 x + 147

my teacher keeps telling me they're wrong without really telling me what I need to fix, just telling me where I messed up

Sounds more like a boss than a teacher.

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In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Bob

Administrator

Registered: 2010-06-20

Posts: 10,621

Re: I Need Help With a Few Algebra Questions!

hi slowlyfading

To help your understanding, I recommend you look at the MIF pages

http://www.mathsisfun.com/equation_of_line.html

http://www.mathsisfun.com/algebra/line- … slope.html

and

http://www.mathsisfun.com/data/straight_line_graph.html

Bob

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Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

SlowlyFading

Member

Registered: 2012-06-12

Posts: 149

Re: I Need Help With a Few Algebra Questions!

Haha, thanks BobbyM and Bob Bundy!

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I'm just here to get some help with an online math course I'm taking.

Bob

Administrator

Registered: 2010-06-20

Posts: 10,621

Re: I Need Help With a Few Algebra Questions!

You are welcome.

Bob

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Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: I Need Help With a Few Algebra Questions!

Hi SlowlyFading;

That should stop the fading.

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In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.