SOLUTION: I really need help with these two problems. Thank you in advance. Simplify and rationalize the denominator where necessary. a) {{{ sqrt( 90 ) / sqrt( 3 ) }}} b) {{{ 15/ 3 +

Algebra ->  Square-cubic-other-roots -> SOLUTION: I really need help with these two problems. Thank you in advance. Simplify and rationalize the denominator where necessary. a) {{{ sqrt( 90 ) / sqrt( 3 ) }}} b) {{{ 15/ 3 +      Log On


   

Question 291203: I really need help with these two problems. Thank you in advance.
Simplify and rationalize the denominator where necessary.
a) +sqrt%28+90+%29+%2F+++sqrt%28+3+%29+
b) +15%2F++3+%2B+sqrt%28+5+%29+ (Note: the ++sqrt%28+5+%29+ is supposed to be part of the denominator but I couldn't get it to go under the line; hope your still able to figure it out.)
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Simplify and rationalize the denominator where necessary.
a) +sqrt%28+90+%29+%2F+++sqrt%28+3+%29+
= sqrt%2890%2F3%29
= sqrt%2830%29
-------------------
b) +15%2F++%283+%2B+sqrt%28+5+%29%29+
Multiply NUM and DEN by the conjugate of the DEN 3 - sqrt(5)
= 15%283-sqrt%285%29%29%2F%289+-+5%29
= 15%283-sqrt%285%29%29%2F4