Explain how you can use base-ten blocks to find 1.54+2.3

The figures below are made out of circles, semicircles, quarter circles, and a square. find the area and the perimeter of each figure and give your answers as a completely simplified exact value in terms of π (no approximations).

Which of the following represents the length of a diagonal of this trapezoid?

Which best explains why this triangle is or is not a right triangle ?