5x – y = 14 2x + y = 7 Solve by adding the equations. = 5x – y = 14 2x + y = 7 Solve by adding the equations. 7x = 21 x = 2( Sub in equation 1 5x – y = 14 2x + y = 7 ) + y = 7 Solve by adding the equations. 7x = 21 x = 3 Sub in equation 1 5x – y = 14 2x + y = 7 6 + y = 7 Solve by adding the equations. 7x = 21 x = 3 y = – x + y = 3 x + 4y = 18 Solve by subtracting the equations. – = – – x + y = 3 x + 4y = 18 Solve by subtracting the equations. – 3y = 15 y = – Sub in equation 2 – x + x + y = 3 x + 4y = 18 Solve by subtracting the equations. – 3y = 15 y = 5 = 3 – Sub in equation 2 – x + y = 3 x + 4y = 18 x + 5 = 3 Solve by subtracting the equations. – 3y = 15 x = y = 5 – – 3x + 2y = 36 3x – 3y = 21 Solve by subtracting the equations. – = – [Spot the double negative] – 3x + 2y = 36 3x – 3y = 21 Solve by subtracting the equations. – 5y = 15 y = – 3x + 2( – Sub in equation 1 3x + 2y = 36 3x – 3y = 21 Solve by subtracting the equations. – 5y = 15 y = 3 ) = 36 – – Sub in equation 1 3x + 2y = 36 3x – 3y = 21 Solve by subtracting the equations. 3x + 6 = 36 – 3x = 5y = 15 y = 3 – – Sub in equation 1 3x + 2y = 36 3x – 3y = 21 3x + 6 = 36 Solve by subtracting the equations. – 3x = 30 5y = 15 y = 3 x = – |