Help! Simplfy! Will mark brainlist!​

Simplify 5 square root of 7 end root plus 12 square root of 6 end root minus 10 square root of 7 end root minus 5 square root of 6 . (1 point) 5 square root of 14 end root minus 7 square root of 12 5 square root of 7 end root minus 7 square root of 6 7 square root of 12 end root minus 5 square root of 14 7 square root of 6 end root minus 5 square root of 7

Simplify (a/b - b/a) times (a - a^2/a+b) a - a^2/a=b is a mixed number

Solve the given system of equations. 2y= -x+9 , 3x-6= -15