Select the values that are solutions to the inequality x2 + 3x – 4 > 0. Question Select the values that are solutions to the inequality x2 + 3x – 4 > 0. in progress 0 Math Mia 2 weeks 2021-09-09T12:37:00+00:00 2021-09-09T12:37:00+00:00 2 Answers 0

## Answers ( )

Answer:see explanation

Step-by-step explanation:Solve the equation

x² + 3x – 4 = 0 ← in standard form

(x + 4)(x – 1) = 0 ← in factored form

Equate each factor to zero and solve for x

x + 4 = 0 ⇒ x = – 4

x – 1 = 0 ⇒ x = 1

The zeros are x = – 4 and x = 1

These split the domain into 3 intervals, that is

( – ∞ , – 4), (- 4, 1), (1 , +∞)

Choose a rest point in each interval, substitute into the quadratic and check the sign.

x = – 5 : (- 5 + 4)(- 5 – 1) = (- 1)(- 6) = + 6 > 0

x = 0 : (0 + 4)(0 – 1) = (4)(- 1) = – 4 < 0

x = 5 : (5 + 4)(5 – 1) = (9)(4) = 36 > 0

Hence x² + 3x – 4 > 0 has solution

(- ∞, – 4) ∪ (1, + ∞ )

Answer is

-6 and 5on edge