Question

What is the first step of equations using elimination?
y=3/4x+3; 2x-4y=6

Answer 1

Will medal best answer

Answer 2

A. Write the second equation in slope-intercept form
B. Subtract 2x from both sides of the second equation
C. Write the first equation in standard form
D. Multiply the first equation by 3

Answer 3

y = 3/4x + 3 -- change to standard form
-3/4x + y = 3 -- multiply by -1 to make x positive
3/4x - y = -3

Answer 4

answer C

Answer 5

Thank you but why -1?

Answer 6

slope intercept form is y = mx + b...not -y - mx + b.

-3/4x + y = 3 --- multiply by -1
(-1) -3/4x + (-1)y = (-1)3
3/4x - y = -3

Answer 7

I suppose you could still do the problem even if you left x negative

Answer 8

So how would I solve a problem like this 2x+3y=13; -6x+4y=0?

Answer 9

ooops..typo up there
I meant to say standard form is Ax + By = C and x needs to be positive.
=======================

2x + 3y = 13 --->(3)
-6x + 4y = 0
--------------
6x + 9y = 39 (result of multiplying by 3)
-6x + 4y = 0
--------------add
13y = 39
y = 39/13
y = 3

now sub 3 in for y in either equation to find x
2x + 3y = 13
2x + 3(3) = 13
2x + 9 = 13
2x = 13 - 9
2x = 4
x = 2

check..
-6x + 4y = 0
-6(2) + 4(3) = 0
-12 + 12 = 0
0 = 0 (correct)

so x = 2 and y = 3

Answer 10

Wow thank you so much!

Answer 11

no problem :)

Answer 12

Hahaha just lost my tooth