What is the solution set for 3x2 plus 4x 15 equals 0?

Answer 1

3x2 + 4x - 15 = 0, solve by using the quadratic formula.

a = 3, b = 4, c = -15

x = [-b ± √(b2 - 4ac)]/(2a)

x = [-4 ± √(42 - 4*3*-15)]/(2*3) = [-4 ± √(16 + 180)]/6 = (-4 ± √(196)/6 = (-4 ± 17)/6

x = (-4 +17)/6 = 13/6 or x = (-4 - 17)/6 = -21/6 = -7/2

The solution set: {-7/2, 13/6}.