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What is the x-coordinate of the solution for the system of equations?
{y−x=9
10+2x=−2y
Enter your answer in the box.

Respuesta :

Assuming given
y−x=9  .................(1)
10+2x=−2y ..........(2)

subtract y from (1) and double
y-x-y=9-y..... double
-2x=18-2y ...........(1a)

(2)-(1a)
10+2x-(-2x)=-2y-(18-2y) =>
10+4x = -18
4x = -18 -10 = -28
x=-7

Answer:

i do man

Step-by-step explanation: