Solution =( -2, 3)
1) Solving that Linear System by Addition/Elimination method:
4x+5y=7 x (-3) To eliminate x
3x-2y=-12 x(4) TO eliminate x
-12x -15y = -21
12x -8y = -48
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-23y = - 69 Divide both sides by -23
y = 3
2) Plug y=3 into the simpler equation, (with lower coefficients)
3x -2y= -12
3x -2(3) = -12
3x -6 =-12 Add 6 to both sides
3x= -12 +6
3x = -6 Divide both sides by 3
x= -2
3) So the answer is S=( -2, 3)
