Question

Simplify the radical 7√7-2√28

Answer 1

ANSWER

$3 \sqrt{7}$

EXPLANATION

The given radical is

$7 \sqrt{7} - 2 \sqrt{28}$

Remove the perfect square from the second radical.

$= 7 \sqrt{7} - 2 \sqrt{4 \times 7}$

$= 7 \sqrt{7} - 2 \sqrt{4} \times \sqrt{7}$

$= 7 \sqrt{7} - 2 \times 2 \times \sqrt{7}$

$= 7 \sqrt{7} - 4 \sqrt{7}$

Subtract the like radicals

$= 3 \sqrt{7}$

Answer 2

Answer:

7√7-2√28 = 3√7

Step-by-step explanation:

We have given the expression:

7√7-2√28

We have to simplify the expression.

As we know that:

√28 = √4×7

Then we have,

7√7-2√28 = 7√7-2√4×7

7√7-2√28 = 7√7-2√4×√7

7√7-2√28 = 7√7-2×2×√7

7√7-2√28 = 7√7-4√7

7√7-2√28 = 3√7