Question

Solve the system by substitution. y=-x^2+2x+10 y=x+4

A. (3,7), (-2,2)
B. (-1,3), (2,6)
C. (0,4), (4,8)
D. (1,5), (5,9)

Answer 1

the answer is A (3,7),(-2,2).

Answer 2

Option A.

Explanation:

System of equations is

-x² + 2x + 10 = y -------(1)

and y = x + 4 ---------(2)

By substituting the value of y from equation 2 to equation 1

-x² + 2x + 10 = x + 4

-x² + 2x - x + 10 - 4 = 0

-x² + x + 6 = 0

x² - x - 6 = 0

x² - 3x + 2x - 6 = 0

x(x - 3) + 2(x + 3) = 0

(x - 3)(x + 2) = 0

x = 3, -2

Now in the given options for x = 3, -2, values of y will be = 7, 2

Option A. will be the answer.