Steply

Simplify 8√18 / 2√2

Step by step, with the reason for every step · Dividing square roots · Algebra 1

Step by step

The question

Question: simplify 8√18/2√2.

8√182√2

1 One root

Rule: a root over a root is the root of the fraction.

√a√b = √ab

The numbers outside make their own fraction.

The roots go under one root.

= 82 × √182

18 divided by 2 is 9.

8/2 is 4.

18 ÷ 2 = 9, 8 ÷ 2 = 4

So we get 4√9.

= 4√9

2 Simplify the root

9 is a square number: 3 times 3 is 9.

So √9 is 3.

3 × 3 = 9

4 times 3 is 12.

So the answer is 12.

= 12

Careful!

18 divided by 2 is 9.

But the answer is the ROOT of 9.

Don't drop the root.

Careful: not √18√2 = 9 ✗

3 Check

Let's check with a calculator.

The start is about 12.00.

Start: 8√182√2 ≈ 12.00

The answer is about 12.00 too.

So it is right!

Answer: 12 ≈ 12.00

Let's look back.

First: one root.

Then: simplify the root.

Last: check.

Answer
= 12

Your turn

Try this one yourself, then check:

12√182√2
Show the answer
18

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