Question

When solving the system x + 2y = 9 and x - y = 6, which expression could be substituted for x in the first equation?
Answer

9 - x

y - 9/2

9 - 2y

1/2 y + 9

Answer 1

Its 9-2y

Answer 2

how do you know?

Answer 3

Because you subtract y from both sides to get X alone.

Answer 4

okay thanks!
what about this one Solve the system. What is the value of x?
y = 3x and 4x + 2y = 30
Answer

3

-3

9

-9

Answer 5

- y + 4x + 2y = - 3x + 30
y = 30 - 7x

30 - 7x = 3x
10x = 30
x = 3
So your answer is 3.

Answer 6

thanks!

Answer 7

Your welcome :)