Question 79449
To solve this we first need to invoke the formula for the area of a rectangle.
area = length * width
or
area = a*b

We know that one side is {{{sqrt(3)+sqrt(5)}}}, and the same goes for the other side. Hence we get:
{{{a = sqrt(3)+sqrt(5)}}}
and
{{{b = sqrt(3)+sqrt(5)}}}

Now all we need to do is to multiply a together with b, including the WHOLE expression and setting it in parentheses.

As we may see here:
{{{area = a*b = (sqrt(3)+sqrt(5))*(sqrt(3)+sqrt(5))}}}
Continuing, we need to multiply each element in the first parenthesis with all the elements in the second. We then get:
{{{area = (sqrt(3)+sqrt(5))*(sqrt(3)+sqrt(5)) = sqrt(3)sqrt(3)+sqrt(3)sqrt(5)+sqrt(5)sqrt(3)+sqrt(5)sqrt(5) = 3 + sqrt(3)sqrt(5) + sqrt(3)sqrt(5) + 5 = 3 + 5 + 2sqrt(3)sqrt(5) = 8 + 2sqrt(3)sqrt(5)}}}

I hope this clarified things for you.

Best regards,
Eric