Question 230400
3x-y=-2
5x+2y=15
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|3 -1 +2|
|5 +2 -15|
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Det = 
|3 -1|
|5 +2|
= 3*2 - 5*-1 = 6+5
Det = 11
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x:
|-1 +2|
|+2 -15|
= 15 - 4 = 11
11/Det = 1
x = 1
--------
-y:
|3 +2|
|5 -15|
= -45 - 10 = -55
-55/11 = -5
-y = -5
y = 5