What is the value of x? show all of your work.

Because the triangle in the picture is a right angle triangle, we can use the Pythagorean theorem to solve the unknown side.

The Pythagorean states that if you take the legs of a right triangle and square them and add them up, they will equal the hypotenuse squared.

In a mathematical equation: 

In this problem, we know the length of one leg and we know the length of the hypotenuse.

The variables a and b in the equation  are the legs. So, they are interchangeable. But the c variable is the hypotenuse.

Plug in the values.



Solve for b.





b = 9

So, the unknown side is 9 units long.

Think of it as five or above give it a shove. change the 5 or above to the right to a zero and add one to the number on the left.