Question 190598
{{{3*sqrt(5x)-sqrt(45x)-4*sqrt(20x)}}} Start with the given expression.
 


{{{3*sqrt(5x)-sqrt(9*5x)-4*sqrt(4*5x)}}} Factor 45 into 9*5 and 20 into 4*5



{{{3*sqrt(5x)-sqrt(9)*sqrt(5x)-4*sqrt(4)*sqrt(5x)}}} Break up the square roots.



{{{3*sqrt(5x)-3*sqrt(5x)-4*2*sqrt(5x)}}} Take the square root of 9 to get 3. Take the square root of 4 to get 2



{{{3*sqrt(5x)-3*sqrt(5x)-8*sqrt(5x)}}} Multiply



{{{(3-3-8)*sqrt(5x)}}} Factor out the GCF {{{sqrt(5x)}}}



{{{-8*sqrt(5x)}}} Combine like terms.




So {{{3*sqrt(5x)-sqrt(45x)-4*sqrt(20x)=-8*sqrt(5x)}}} where {{{x>=0}}}