Respuesta :

kathrynlizzy

Answer:

x = -1 and y = 6

Step-by-step explanation:

y = x + 7

5x + 2y = 7

y - x = 7.............(1)

2y + 5x = 7......(2)

multiply equation (1) by 2

2y - 2x = 14

2y + 5x = 7

subtract equation (2) from (1)

2y - 2x = 14

- 2y + 5x = 7

-------------------

0 -7x = 7

-7x = 7

divide both sides by 7

-7x = 7

----- ----

7 7

-x = 1 multiply through by minus sign

x = -1

substitute x = -1 into equation (1)

y - x = 7

y - (-1) = 7

y + 1 = 7

y = 7 - 1

y = 6