Solve the simultaneous equations. 2x + y = 18, x − y = 6
1.Isolate either x or y. in this example you can do this by moving adding y to both sides of the second equation x-y=6 becomes x=6+y
2.substitute this into the other equation 2(6+y) + y = 18
3.simplify this (with the aim of finding Y)first expand the brackets12+2y+y=18rearrange by adding 2y and y and subtracting 12 from each side of the equation3y=6find y by dividing both sides by 3Y = 2
4. substitute this into the worked equation (x=6+y) to find XX=6+2X=8
SR
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