a) Use substitution to solve the equations 3x - y = 4 x - 2y = -1 b) A circle has centre at (-6, 12) and passes through (14,-9). Find the equation of the circle. Give your answer in the form x + y+fx+gy+h=0 where f,g and h are integers. c) If (4x2+6x+6k) is divided by than the remainder when (2x2 (2x-1), the remainder is 2 times larger 3x + k) is divided by (x + 2). Use the Remainder Theorem to find the value of k.