Solve simultaneously 2x + 3y = 18 and y = 3x – 5 to find the value of x and y.
sub the y value into the first eqn 2x + 3(3x-5) = 18 expand the brackets 2x +9x-15 = 18 add up the x values 11x -15 = 18 add 15 to both sides to cancel it out on the l.h.s 11x = 33 divide by 11 to get value of x x = 3 put value of x into the y eqn y = 3(3) - 5 work out value of y y = 4
JG
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