Question

What are the solutions of 3x2 + 6x + 15=0 ?

Answer 1

x = -1 ± 2i

Explanation:

Quadratic Formula:
`x = (-b+/-√(b^2-4ac) )/(2a)`

√-1 = i

Step 1: Factor GCF

3(x² + 2x + 5)

Step 2: Use quadratic formula

a = 1

b = 2

c = 5

`x = (-2+/-√(2^2-4(1)(5)) )/(2(1))`

`x = (-2+/-√(4-20) )/(2)`

`x = (-2+/-√(-16) )/(2)`

`x = (-2+/-i√(16) )/(2)`

`x = (-2+/-4i )/(2)`

`x = (-2(-1+/-2i) )/(2)`

x = -1 ± 2i