Solve the Simultaneous equations '2x-3y=24' and '6x+2y=-5'
To solve you must make sure there are the same number of either x's or y's in both equations. We will call '2x-3y=24' equation 1, and '6x+2y=-5' equation 2. If you multiply equation 1 by 3 then you get '6x-9y=72'. Now both equations have 6x, next you need to get rid of the x. In this case we will subtract equation 1 from equation 2. This gives '6x+2y-(6x-9y)=-5-72. If you simplify this it gives '11y=-77' and dividing by common factors (11) gives 'y=-7'. This can then be put into the original form of equation 1 to find x. '2x-3*(-7)=24', '2x+21=24', '2x=3', 'x=1.5'You should always check your answer by putting the values of x and y into the other equation (in this case equation 2 and checking it is correct. e.g. '61.5+2(-7)=-5', '9-14=-5'
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