Question

simplify root 63 minus 5 root 28 + 11 root 7

Answer 1

Given,

$\sqrt{63} - 5\sqrt{28} + 11\sqrt{7} \\ \\ = \sqrt{9 \times 7} - 5\sqrt{7 \times 4} + 11\sqrt{7}  \\ \\ = 3\sqrt{7} - 5*2\sqrt{7} + 11\sqrt{7} \\ \\ = 3\sqrt{7} - 10\sqrt{7} + 11\sqrt{7}  \\ \\ = \sqrt{7}(3 - 10 + 11)  \\ \\ = 4\sqrt{7} \ \ \textbf{Ans.}$

Answer 2

√63 - 5 √28 + 11 √7

= √9*7 - 5√4*7 + 11√7

= As √9 = 3 and √4 = 2 to make is simpler we can write it as 3 and 2 respectively.

√3*7 - 5√2*7 + 11√7

As 7 is common in all the equations and if we take the 7 outside we will have this:

3√7 - 5*2√7 + 11√7

= 3 √7 - 10√7 + 11√7

Now, we can add all the numbers except the 7

3-10 +11 (√7)

= 3 √7

I hope this helps you understand!