Assume you mean 3x^2 when you typed the question.
3x^2+14x+16=0
(3x+8)(x+2)=0
x=-8/3 or -2
Answer:
<h2>x = 5.7</h2>
Step-by-step explanation:

To find x first cross multiply
We have
7x = 8 × 5
7x = 40
Divide both sides by 7
That's


x = 5.7142
We have the final answer as
<h3>x = 5.7 to the nearest tenth</h3>
Hope this helps you
All three triangles are congruent by SAS
x = -4, so use the first equation, x^2 = -4^2 = -16
x = 4, use 3rd equation, sqrt(x) = sqrt(4) = 2