Finding the Length of a Diagonal Without Using a Ruler

This lesson teaches how to find the length of a diagonal by creating a square. It reviews square units and square numbers, discusses common mistakes students make, and explains how to calculate areas of squares. The lesson also covers methods to find diagonal lengths without using a ruler, emphasizing the importance of counting units and understanding square roots.

What is the area of a square with side length 5 cm?

• 20 cm²

• 25 cm²

• 15 cm²

• 10 cm²

How many square units are inside a square with side length 4 cm?

• 20 square units

• 16 square units

• 12 square units

• 8 square units

What is the square root of 49?

• 6

• 7

• 5

• 8

How can you find the length of a diagonal without using a ruler?

• By measuring the sides with a ruler

• By calculating the square root of the area

• By counting the number of squares

• By estimating visually

What is the area of a square with side length 2 cm?

• 2 cm²

• 4 cm²

• 8 cm²

• 6 cm²