Find the lowest common denominator 1/((a + 1) ^ 2), 1/((a - 1) ^ 2), 2/(a ^ 2 - 1)

Solve the system of equations. y= 2x y= x^2 - 15

Can some one me with these questions

Over the last 4 seconds, a snail has traveled 4/9 of an inch. if the snail traveled the same distance each second, how far did it travel each second?