Answer: Choice A
The area of square T is equal to the sum of the areas of square R and square S.
=======================================================
Step-by-step explanation:
Recall that the pythagorean theorem says
a^2+b^2 = c^2
Visually this means if we had a square with side length 'a', then its area is a^2. The same goes for a square with side length b. Its area is b^2
So a^2+b^2 is the sum of those square areas. It being equal to c^2 tells us that adding the smaller square areas lead to the largest square area.
So that's why the areas of squares R and S add up to the area of square T.
--------------
An example:
Let's say...
- square R has side length 3
- square S has side length 4
- square T has side length 5
note how 3^2+4^2 = 9+16 = 25 and how 5^2 = 25. This shows 3^2+4^2 = 5^2