SOLUTION: Use Cramer's Rule to solve this equation. 2x-5y=18 -x+3y=10

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Question 39449: Use Cramer's Rule to solve this equation.
2x-5y=18
-x+3y=10
Answer by longjonsilver(2297) About Me  (Show Source):
You can put this solution on YOUR website!
M = +matrix%282%2C2%2C%0D%0A2%2C-5%2C%0D%0A-1%2C3%0D%0A%29+

Its determinant, D is:
D = (2)(3)-(-1)(-5)
D = 6-5
D = 1

Now repeat on
+matrix%282%2C2%2C%0D%0A18%2C-5%2C%0D%0A10%2C3%0D%0A%29+

Dx = (18)(3)-(10)(-5)
Dx = 54+50
Dx = 104

and also on
+matrix%282%2C2%2C%0D%0A2%2C18%2C%0D%0A-1%2C10%0D%0A%29+

Dy = (2)(10)-(-1)(18)
Dy = 20+18
Dy = 38

So, x = Dx/D
--> x = 104/1
--> x = 104

So, y = Dy/D
--> y = 38/1
--> y = 38

CHECK:
2x-5y
2(104)-5(38)
208-190
18... CORRECT

and -x+3y
-(104)+3(38)
-104+114
10... CORRECT

jon.