Question

Use the substitution method to solve the system of equations. Choose the correct ordered pair.

y = 3x - 4
x = 9

A. (9, 23)
B. (1, -1)
C. (0, -4)
D. (9, 31)

Answer 1

This is like the last one we did @Tallan

Answer 2

Do you understand what substitution means?

Answer 3

Ok so i know that 9 is x

Answer 4

Just input in 9 for x in the above equation

Answer 5

You're "substituting" in 9 for x

Answer 6

Yep. Since x is already solved (given) it is a very simple substitution. =)

Answer 7

y = 3(9) - 4

Answer 8

Try solve for it.

Answer 9

23

Answer 10

y = 23 is correct

Answer 11

So it would be A. (9,23) right?

Answer 12

Yep c;

Answer 13

Remember to check your answers though ;p

Answer 14

Yah, well, with one being given there is not much to check.

Answer 15

23 = 3(9) - 4

23 = 27 - 4

23 = 23

Correct

9 = 9

Kinda obvious ;P

Answer 16

@e.mccormick Just get them used to the habit of checking their work

Answer 17

Yep. Substitution can generally be done two ways... this one is just one. If you can do it both ways and come out the same, it is (usually) good!