Solve the simultaneous equations: 4x+5y=13 and 3x-2y=27


Equation 1 is 4x+5y=13 - multiply it by 3, Equation 2 is 3x-2y=27 - multiply it by 4, New equation 1 is 12x+15y=39, New equation 2 is 12x-8y=108, Subtract new equation 2 from new equation 1 - 23y=-69 therefore y=-3, Substitute y=-3 into equation 1 - 4x+(5x-3)=13, 4x-15=13, 4x=28, x=7. Final answer: x=7, y=-3

TD

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