Name: Simplifying square roots: solution walkthrough
Uploaded: 2026-11-13
Duration: 1 min 29 s
Description: Which of the following is equal to √72? Try it, then watch the animated solution.

A square with area

72

has side length

\sqrt{72}

. Cut the square into smaller equal squares to simplify it.

Look for a perfect square inside

72

:

72 = 36 \times 2

, and

36 = 6 \times 6

.

Each small square has area

2

, so its side is

\sqrt{2}

. The

36

squares sit

6

to a side.

The big side is

6

small sides in a row:

\sqrt{72} = 6\sqrt{2}

.

Traps:

36\sqrt{2}

forgets to take the root of

36

,

2\sqrt{6}

swaps the numbers, and

36

is just

72 \div 2

.

Try it first