Question

solve √45 × √20 ≈ find

Answer 1

Answer:

30

Step-by-step explanation:

We have,

$\sqrt{45} \times \sqrt{20}$

$= \sqrt{9 \times 5} \times \sqrt{4 \times 5}$

$= \sqrt{3 \times 3 \times 5} \times \sqrt{2 \times 2 \times 5}$

$= \sqrt{ {(3)}^{2} \times 5} \times \sqrt{ {(2)}^{2} \times 5}$

$= 3 \sqrt{5} \times 2 \sqrt{5}$

$= (3 \times 2) \times ( \sqrt{5} \times \sqrt{5} )$

$= 6( \sqrt{5 \times 5} )$

$= 6[ \sqrt{ {(5)}^{2} } ]$

$= 6 \times 5$

$= 30$