SOLUTION: How would u solve this problem by using inverse matrix: 17x+4y=76 21x+5y=94

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Question 384097: How would u solve this problem by using inverse matrix:
17x+4y=76
21x+5y=94
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
[A]=%28matrix%282%2C2%2C17%2C4%2C21%2C5%29%29
[x]=%28matrix%282%2C1%2Cx%2Cy%29%29
[b]=%28matrix%282%2C1%2C76%2C94%29%29
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[A][x]=[b]
[x]=[A]inv[b]
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det[A]=17%2A5-21%2A4=1
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[A]inv=%28matrix%282%2C2%2C5%2C-4%2C-21%2C17%29%29
[x]=[A]inv[b]==%28matrix%282%2C2%2C5%2C-4%2C-21%2C17%29%29%2A%28matrix%282%2C1%2C76%2C94%29%29
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[x]=%28matrix%282%2C1%2C4%2C2%29%29