How do I solve the factor expression using the GCF for 2+8

The radical equation 2+√2x-3 = √x+7 has a solution set [x= a0} and an extraneous root x = a1.

Amountain climber starts a climb at an elevation of 453 feet above sea level at his first rest stop he has climbed 162 feet and by his second rest stop he has climbed another 207 feet its getting late in the day so the climber starts his way down if the climber desends 285 feet how much does he need to ascend or descend to return to the original starting point

One side of a rectangle is 7 centimeters shorter than six times the other side. find the length of the longer side if we also know that the perimeter of the rectangle is 266 centimeters.