Hey there!
Let's solve the equation step by step!
![3 x^(2) + 4 = 40](https://img.qammunity.org/2019/formulas/mathematics/middle-school/7jch46efnatoypp4ggueamk7qux0ti6wgl.png)
Subtract 4 from both sides.
![3 x^(2) = 36](https://img.qammunity.org/2019/formulas/mathematics/middle-school/zeiaq6q1dyojlcj2sxuijgo24udfb54gyo.png)
Divide both sides by 3.
![x^(2) = 12](https://img.qammunity.org/2019/formulas/mathematics/middle-school/trvojw2qhledclck3z5nvu852l1gyk1py3.png)
Solve the equation by taking the positive and negative root of 12.
![x = √(12) = 2 √(3) = 3.46... \\or\\ x = - √(12) = -2 √(3) =3.46...](https://img.qammunity.org/2019/formulas/mathematics/middle-school/9kprz79rk1tdg9b08pyo9l2dxumepe9msm.png)
The exact answer includes the roots, the other answer is the answer in two decimals.
~Hope this helps you!