Question

Could someone please help me with #7 and #8?

Answer 1

7. Plug in 3x + 8 for y in second equation
2(3x + 8) = 6x + 16
6x + 16 = 6x + 16
It would be all solutions

8. Plug in 4x + 5 for y in second equation
12x - 3(4x + 5) = 9
12x - 12x - 15 = 9
12x cancels out
-15 = 9
There would be no solution

Answer 2

Answer: I'm not sure If i'm right because I did this since 8th grade.

For number 7, I think it would be (the equation form)= 6 x  +  16

For number 8, I think it would be nothing because there is no solution.

Hope this helps:)