Question

x + y = 15
4x + 6y = 72

Answer 1

I need help again finding x then plugging it in to find y

Answer 2

Use Wolfram|Alpha

Answer 3

(1)*6: 6x+6y=90 ---(3)
(3)-(2): 2x=18 --> x=9

Answer 4

subtract y from both sides in the first equation and then substitute for x.

Answer 5

method of @AlexisEyvonne also works :)

Answer 6

I need help with another please :)

Answer 7

3x + 2y = 475
x + 2y = 180

Answer 8

(1)-(2): 2x=295 --> x=147.5