Solve the simultaneous equations. 2x + y =10 and x + y = 4
We should eliminate one of the variables. We do this by writing them on top of one another.3x + y = 10x + y = 4 -
2x = 6 We want to know what X is and what Y is. We currently know what 2x is so we divide the answer by 2.
x = 3
To find out what y is, we substitute 3 into one of the equations.
x + y = 43 + y = 44 - 3 = yy = 1
We then use the other equation to check if we are correct.
3x + y = 10(3 x 3) + 1 = 109 + 1 = 10
GN
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