What is the sum of (4x2 – 10x + 3) and (-6x2 + 10x + 12)

-2x² + 15

Step-by-step explanation:

Step 1: Add like terms

4x² - 6x² = -2x²

-10x + 10x = 0

3 + 12 = 15

Step 2: Rewrite

-2x² + 15

x = -3

y = -18

step-by-step explanation:

to solve by substitution, substitute one variable and solve for the other. then substitute again to find the remaining variable.

x-1/3(3x-9) = -3 since y=3x-9 substittute y.

x-1/3(3x-9)=-3

x + x +3 = -3

2x+3=-3

2x+3-3= -3-3

2x=-6

x=-3

substitute again into y=3x-9

y=3(-3)-9

y=-9-9

y=-18

the answer is b. 60. each interior angle in 120, so the exterior angle must be 60 in order to add up to 180

step-by-step explanation: