What are the approximate solutions of 4x2 + 3 = −12x to the nearest hundredth?

x ≈ −3.23 and x ≈ 0.23

x ≈ −2.72 and x ≈ −0.28

x ≈ 0.28 and x ≈ 2.72

x ≈ −0.23 and x ≈ 3.23

Question

What are the approximate solutions of 4x2 + 3 = −12x to the nearest hundredth? 

 x ≈ −3.23 and x ≈ 0.23 

 x ≈ −2.72 and x ≈ −0.28 

 x ≈ 0.28 and x ≈ 2.72 

 x ≈ −0.23 and x ≈ 3.23

campbell_st · Answer

rewrite the equation as 

4x^2 + 12x + 3 = 0

use the general quadratic formula

$$x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} $$

in your question a = 4, b = 12 and c = 3

substitute and evaluate

anonymous · Answer

180 SR 13.41
2 * 4 = 8
13.41 / 8

anonymous · Answer

1.67

anonymous · Answer

@campbell_st

campbell_st · Answer

$$x = \frac{ -12 \pm \sqrt{144 - 48}}{8}$$

and just use the calculator to get an answer