Answer:
x = 21
Explanation:
We can first notice that this is a right triangle. Meaning that we can apply the pythagorean theorem when finding the missing side.
Pythagorean Theorem : a^2+b^2=c^2
But, we already have the hypotenuse, so we have to solve for the side being "b". a and b being the sides next to the right angle. And c being the hypotenuse. Plug in the values.
20^2 + b^2 = 29^2
400 + b^2 = 841
Subtract 400 from both sides to get b^2 alone
-400 -400
b^2 = 441
Square root of each side to get b by itself
b = 21
This means the missing side is 21. Also meaning 21 is x.
x = 21