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## #1 This is Cool » A new formula » 2022-10-01 19:39:13

Abbey78336
Replies: 0

Just like the quadratic formula. I have made a linear formula as i was thinking through how the quadratic formula (making x the subject of ax^2 + bx + c = 0) so i also made x the subject of the standard linear equation

y=mx+c
y-c=mx+c-c
y-c=mx
(y-c)/m=(mx)/m
(y-c)/m=x

PROOF
Solve;
1) 15=2x+3
x=(y-c)/m
x=(15-3)/2
x=12/2
x=6      CORRECT

## #2 Help Me ! » Negative second degree equation » 2022-10-01 19:00:45

Abbey78336
Replies: 6

Can any one solve this ?

2x^(-2) + 5x + 10 = 0

## #3 Help Me ! » How many dollars ? » 2022-09-20 05:25:25

Abbey78336
Replies: 3

If Two US pennies Weigh as one quater. 4 kg of US pennies make \$100 4 kg of US quaters will make ????

## #4 Re: Help Me ! » Solve » 2022-09-03 19:15:55

You are not helping me all i want is the cubic formula but you are just giving other explanations i have been studying equations of math for 6 months i know almost everything other than the cubic formula pleaseeeeeeeeee!! I need the cubic formula if it is not there lets make it maths is made by p'ple like us if you can't it means you are ./.?.¡.\.:.".. Nothing

## #5 Re: Exercises » Make x the subject of the formula! » 2022-09-03 18:48:51

The question said make x the subject of the formula NOT what is this type of equation

## #6 Exercises » Make x the subject of the formula! » 2022-09-03 00:41:00

Abbey78336
Replies: 2

Make x the subject of the ax^3 + bx^2 + cx = -d

## #7 Maths Is Fun - Suggestions and Comments » How can i upgrade ? » 2022-09-02 00:17:44

Abbey78336
Replies: 1

How can i become a pm or an administrator

## #8 Exercises » Find the perimeter of the square » 2022-09-01 22:16:50

Abbey78336
Replies: 3

A square with a side (x+7)cm and its area as 33cm^2 find its perimeter

## #9 Formulas » Cubic formula » 2022-09-01 22:03:34

Abbey78336
Replies: 1

Has anyone of you ever heard of the cubic formula. Or ever dreamt of it existing so cubic equations could be easily solved. Let our dreams come true. I have been working on it recently but i can't do it alone. I request anyone with an idea to start. We can make a cubic formula. Waiting for your help

## #10 Re: Help Me ! » Solve » 2022-09-01 20:55:03

Is there a formula like a the quadratic formula where i just plug in the a,b....y,z

## #11 Re: Help Me ! » Solve » 2022-09-01 01:04:38

Wait i have heard of a cubic formula! What is it ¿¿¿¿

## #12 Re: Help Me ! » Solve » 2022-08-31 09:41:05

I have used an online cubic equation solver giving a = 2 b = 0 c = 1 d = -171 and got 3 solutions
[-2.1838+3.84798i]
[-2.1838-3.84798i]
[4.3676] try proving it

## #13 Re: Help Me ! » Solve » 2022-08-31 09:30:50

It was from no where i was just thinking through some complex equations and i found this but i think we can solve it as a cubic equation in this way 2x^3 + 0x^2 + x = 171

## #14 Re: Help Me ! » Solve » 2022-08-30 17:49:38

Not a mistake ! So do you mean it can't be solved ?

Abbey78336
Replies: 17

2x^3 + x = 171

## #16 Help Me ! » How many integers » 2022-08-25 04:41:49

Abbey78336
Replies: 1

How many positive integers less than 2002 are a multiple of 3 or 4 but not 5

## #17 Re: Help Me ! » What is the number? » 2022-08-24 21:39:59

So we will use 6 giving 66+2c=76 c=5 and we know that a=3 b=6 c=5 abc=365.
AS SIMPLE AS DYING

Another one

## #19 Re: Help Me ! » What is the number? » 2022-08-24 05:12:47

From where? Step by step

## #20 Help Me ! » What is the number? » 2022-08-24 04:52:39

Abbey78336
Replies: 6

The sum of A number and the sum of its digits is 379. What is the number???????????

## #21 Re: Help Me ! » Help me solve this. 98% of mathematicians failed » 2022-08-21 19:52:00

What if it is 2x^2 + 432/(49x) = 3

## #22 Re: Help Me ! » Help me solve this. 98% of mathematicians failed » 2022-08-20 20:38:19

Sorry I made a mistake it was supposed to be  2x^3 +(432/(49x)) =3

## #23 Re: Help Me ! » Help me solve this. 98% of mathematicians failed » 2022-08-18 21:53:27

Then solve it step by step

## #24 Re: Formulas » common mistake » 2022-08-18 08:17:30

It is not true !

-a^2 is not equal to -1×a^2

PROOF
if a=5 -a^2=(-5)^2=-5×-5=+25 but -1×a^2=-1×5^2=-1×25=-25
So -25 is not equal to +25

## #25 Help Me ! » Help me solve this. 98% of mathematicians failed » 2022-08-18 07:56:32

Abbey78336
Replies: 9

2x^2 + (432/49x) = 3