Question

use the substitution method to solve the system of equations . choose the correct ordered pairs x+y=5 y=7 A.(12,7) B.(-12,7) C. (-2,7) D.(2,7)

Answer 1

(-2,7)

Explanation:

x+7=5

Subtract 7 from 7 and 5.

x=-2

Plug -2 into equation.

-2+y=5

Add 2 to -2 and 5.

y=7

(-2,7)

Answer 2

C. (-2,7)

Explanation:

In substitute method to solve a system of linear equations of two variables, We find the value of one variable from one equation and substitute it into the another equation.

Given system of equations is,

x + y = 5 -----(1),

y = 7 ----(2),

Substitute the value of y from equation (2) to equation (1),

x + 7 = 5

Subtracting 7 on both sides,

x = - 2

Hence, the correct order pair that shows the solution of the given system of equation is,

(x,y) = (-2,7)

Option C is correct.