Ineed solving x^2-2=7 by factoring

The isosceles triangle has two sides of equal length, a, that sre longer than the length of the base ,b. the equation 2a+b=15.7 can be used to find the sides length. if one of the longer sides is 6.3 centimeters what is the length of the base

Pls! does anybody know a shortcut for answering these types of questions in the future?

Which expression is equivalent to7_/x^2 ÷ 5_/y^3? assume y# 0