2x 9 5y 2 July 8, 2019 16 32 64 128 2x 5y 9 3x 2y 4 2x 5y 9 4x 2y 6 2x 5y 9 3x 4y 2 2x 5y 9 x 4y =- 2 X 2y 2x 5y 9 5y 2x 9 y 3x =- 2.1 2x y 9 3x 5y 20 2x 5y 9 y 2 2x 5y 9 2x 3y 7 2x 5y 9 3x 4y 2 simultaneous equation 2x 3y =- 9 x 5y =- 29 2x 5y 9 6x 15y 27 2x 5y 9 0 3x 4y 2 3y 2x 9 2x 5y 15 X 2y 2x 5y 9 substitution