Answer:
x₁ = -4
x₂ = 3
Step-by-step explanation:
x²+ x + 12 = 0
x = {-1±√((1²)-(4*1*-12))} / (2*1)
x = {-1±√(1+48)} / 2
x = {-1±√49} / 2
x = {-1±7} / 2
x₁ = {-1-7} / 2 = -8/2 = -4
x₂ = {-1+7} / 2 = 6/2 = 3
Check:
x₁
-4² + (-4) - 12 = 0
16 - 4 - 12 = 0
x₂
3² + 3 - 12 = 0
9 + 3 - 12 = 0
3- 3, 6, 9, 12, 15, 18, 21, 24, 27, 30
4- 4, 8, 12, 16, 20, 24, 28, 32, 36, 40
7- 7, 14, 21, 28, 35, 42, 49, 56, 63, 70
HOPE IT HELPED