Question

Solve for x. Enter your answer in interval
notation using grouping symbols.
x² + 2x ≥ 15

Answer 1

`(x−3)(x+5) .....is.. the.. factorised.. form.. of.. the.. expression`

Explanation:

`x^2 + 2x > =15 \\x^2 + 2x - 15 > = 0 \\(x + 4)(x - 2) < 0 , \\{x + 4 < 0 and .x - 2 > 0} or {x + 4 > 0 ,\\and .x - 2 < 0} , \\{x < -4 and .x > 2} or {x > -4 and. x < 2},\\ Discard .x < -4 and. x > 2 because. it. has. no. solutions,\\ leaving .just x > -4 and .x < 2 , -4 < x < 2`