Question 761549
how does 1/2 square root of 5 + 1 1/2 square root of 20 equals 7/2 square root of 5?

{{{(1/2)*sqrt(5) + (3/2) * sqrt(20)}}}

=

{{{(1/2)*sqrt(5) + (3/2) * sqrt(4*5)}}}

=

{{{(1/2)*sqrt(5) + (3/2) * sqrt(4) * sqrt(5)}}}  (because sqrt(a*b) = sqrt(a) * sqrt(b)

=

{{{(1/2) * sqrt(5) + 3 * sqrt(5)}}} ---> sqrt(4) = 2

=

{{{(3+1/2) * sqrt(5)}}}

=

{{{(7/2) * sqrt(5) }}}


:)