Find x and y when 3x + 4y = 27 and x + 2y = 11
Use the elimination method to remove a common coefficient.
Multiply one of the equations to find a common coefficient, eg multiply the second equation by 2 to get 2x + 4y = 22, to reach the common coefficient of 4y, then subtract this equation from the first equation.
The result of this subtraction is x = 5.
Then substitute x = 5 into either equation to find the value of y, i.e. 5 + 2y = 11 therefore subtracting 5 from both sides 2y = 6, therefore divide by 2 to get y = 3.
ES
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