$2100 left the ATM ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
You do what is asked for in the parentheses then multiply by the number outside of them.
Unfortunately, this item does not come with any figure to illustrate the lengths of the rectangle. However, it may be noted that by connecting two opposite vertices of a rectangle by a diagonal, we form a right triangle. We may then use the Pythagorean theorem to solve for the answer.
a² + b² = c²
c in this equation is the length of the diagonal, a and b are the lengths of the sides.