Chapter 1: Square Roots and the Pythagorean Theorem

Unit Review

What do I need to know?

Side Length and Area of a Square– The side length of a square is equal to the square

root of its area.– Length = √Area– Area = (Length)2

– **The side length of a square multiplied by itself equals the area. **

side length = 5 units

area = 5 x 5 = 25 units2

5

5

A = 25

You square root the area of a square to find its side length.

√Area = side length

√25 = 55

5

A = 25

What do I need to know?

The Approximate Square Root of a Number– For numbers that are not perfect squares, we can

determine the approximate square root using estimation or a calculator.

– Eg: Place each square root on the number line to show its approximate value: √2, √5, √11, √18, √24

What do I need to know?

right triangle:a triangle with one

right angle.

Hypotenuse:the side opposite

the right angle in

a right triangle

What do I need to know?

The Pythagorean Theorem– In a right triangle, the area of the square on the

hypotenuse is equal to the sum of the areas of the squares on the two legs.

Use the Pythagorean Theorem to find the length of a side in a right triangle, when two other sides are known.

Remember:– If looking for the the hypotenuse, add the squares

of the other sides.– If looking for a leg, subtract the squares of the

other sides.