What is -4 square root of 90 + 2 square root of 160?

1 Answer
Sep 16, 2015

#-4sqrt(10)#

Explanation:

#sqrt(90)#
#color(white)("XX")=sqrt(3^2xx10) = 3sqrt(10)#

#sqrt(160)#
#color(white)("XX")=sqrt(4^2xx10) = 4sqrt(10)#

Therefore
#color(red)(-4sqrt(90)) + color(blue)(2sqrt(160))#

#color(white)("XX")=color(red)((-4)(3sqrt(10))) +color(blue)((2)(4sqrt(10)))#

#color(white)("XX")=color(red)(-12sqrt(10))+ color(blue)(8sqrt(10))#

#color(white)("XX")=-4sqrt(10)#