Question

What is the solution of the system? Use substitution.

4x – y = 5
3x – 7 = 2
A) (3, 7)
B) (7, -7)
C) (-3, 7)
D) (3/4, 2/5)

Answer 1

Hi

We need to solve 3x-7=2 for x

Let's start by adding 7 to both sides

3x-7+7=2+7

3x=9

Now just divide both sides by 3 so we can find the value for x

3x/3=9/3

x=3

Now substitute 3 for x in 4x-y=5 so we can find the value for y

4x-7=5

4(3)-y=5

-y+12=5

Add -12

-y+12-12=5-12

-y=-7

Now divide both sides by -1 so we can find the positive value for y

-y/-1=-7/-1

y=7

The answer is A

(3,7)

Good luck:0