12. Solve x^2 + 6x - 16 = 0 by completing the square.

Please help and show work

x is 2 and -8

Step-by-step explanation:

general equation

sum is 6, product is -16

for completing squares,

first divide the sum by 2:

add the square of the result on (x² + 6x) and subtract it from the product:

take square root:

x is either: 5-3 or -5-3

29.5977692753

step-by-step explanation:

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