3(2x+2)+x+5=-10
6x+6+x+5=-10
7x+11=-10
7x=-21
x=-3
SOLUTION
From the image in the question, we can see that it is a right triangle problem.
And we can use the Pythagoras theorem to solve for the length of cable wire needed.
Pythagoras theorem states that:

![\begin{gathered} x^2=16+9 \\ x^2=25 \\ \text{Take the square roots of both sides:} \\ \sqrt[]{x^2}=\sqrt[]{25} \\ x=5ft \end{gathered}](https://tex.z-dn.net/?f=%5Cbegin%7Bgathered%7D%20x%5E2%3D16%2B9%20%5C%5C%20x%5E2%3D25%20%5C%5C%20%5Ctext%7BTake%20the%20square%20roots%20of%20both%20sides%3A%7D%20%5C%5C%20%5Csqrt%5B%5D%7Bx%5E2%7D%3D%5Csqrt%5B%5D%7B25%7D%20%5C%5C%20x%3D5ft%20%5Cend%7Bgathered%7D)
Final Answer:
A cable of length 5 feet is needed.
Step-by-step explanation:
numbers one two and three are correct