Question

Solve the following system of equations by substitution. please explain y=-2x+1 3x-2y=5

Answer 1

Answer:

x=1

Step-by-step explanation:

$y= -2x+1\\3x-2y=5$

You substitute $-2x+1$ for y in the second equation, because it is equal to y.

$3x-2(-2x+1)=5\\3x-(-4x+2)=5\\3x+4x-2=5\\7x-2=5\\7x=7\\x=1$

Alternate Method:

set both equations equal to y

$3x-2y=5\\3x-5=2y\\y=\frac{3x-5}{2}$

Then you have

$y=-2x+1\\y=\frac{3x-5}{2}$

And you substitute one of the equations in for y in the other one

$-2x+1=\frac{3x-5}{2}$

multiply both sides by 2

$-4x+2=3x-5$

and solve

$7x=7\\x=1$