Question

Помогите решить, алгебра 8 класс.

Answer 1

$1.;sqrt{27}-sqrt{48}+sqrt{75}=sqrt{9cdot3}-sqrt{16cdot3}+sqrt{25cdot3}=\=3sqrt3-4sqrt3+5sqrt3=4sqrt3\\2.;3sqrt c+8sqrt c-9sqrt c=2sqrt c\\3.;5sqrt a-2sqrt b+sqrt a=6sqrt a-2sqrt b\\4.;sqrt7(5sqrt7+sqrt{14})=sqrt7(5sqrt7+sqrt{2cdot7})=sqrt7(5sqrt7+sqrt{2}cdotsqrt{7})=\=5cdot7+sqrt2cdot7=35+7sqrt2$