Do 8 * 400 = 3,200
Then do 3,200 - 24 = 3,176
Answer:
x = -2 ±sqrt(7)
Step-by-step explanation:
3x^2 +12 x = 9
Divide each side by 3
3x^2 /3 +12x/3 = 9/3
x^2 +4x = 3
Take the coefficient of x
4
Divide by 2
4/2 =2
Square it
2^2 =4
Add it to each side
x^2 +4x+4 = 3+4
x^2 +4x+4 = 7
(x+2)^2 = 7
Take the square root of each side
x+2 = ±sqrt(7)
Subtract 2 from each side
x+2-2 = -2 ±sqrt(7)
x = -2 ±sqrt(7)
