Question

A.(7,8) B.(2,22) C.(2,8) D.(3,29)

Answer 1

Hey there!

To use the substitution method in order to solve the system of equations,
y=7x+8
y=x+20 , first notice that both equations are set equal to the same value, y.

Knowing this, 7x+8 and x+20 both equal the same value so you would set them equal to one another:
7x+8=x+20.

This would be substitution as you are substituting one of the equations in place of y.

Now, solve for x:
7x+8=x+20
6x+8=20
6x=12
x=2

Now that you know x equals the value of 2, you can substitute the value into one of the equations to find y:
y=x+20
y=2+20
y=22

Now that you have x=2 and y=22, you can conclude that your answer would be (2,22) or choice B.

Hope this helps and have a wonderful day! :)