SOLUTION: Problems with Algebra. Evaluate D X+2y=3 3y-x=2 D = ?

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Question 465230: Problems with Algebra.
Evaluate D
X+2y=3
3y-x=2
D = ?

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 
Hi,
Note:


x+2y =3
-x+2y =2
D = %28matrix%282%2C2%2C1%2C2%2C-1%2C2%29%29 = 1*2 - (2*-1) = 2 + 2 = 4
Note: %28matrix%282%2C2%2Ca%5B1%5D%2Cb%5B1%5D%2Ca%5B2%5D%2Cb%5B2%5D%29%29= a%5B1%5Db%5B2%5D-a%5B2%5Db%5B1%5D