SOLUTION: How do you solve this problem. It asks to find the inverse of the matrix. {{{ 7 -4 }}} {{{ -5 3 }}}

Algebra ->  Matrices-and-determiminant -> SOLUTION: How do you solve this problem. It asks to find the inverse of the matrix. {{{ 7 -4 }}} {{{ -5 3 }}}      Log On


   

Question 879488: How do you solve this problem. It asks to find the inverse of the matrix.

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Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
To find the inverse of a 2x2 matrix.
A=%28matrix%282%2C2%2Ca%2Cb%2Cc%2Cd%29%29
Then,
A%5E%28-1%29=%281%2F%28ad-bc%29%29%2A%28matrix%282%2C2%2Cd%2C-b%2C-c%2Ca%29%29
So,
1%2F%28ad-bc%29=1%2F%287%283%29-%28-4%29%28-5%29%29=1%2F%2821-20%29=1
A%5E%28-1%29=%28matrix%282%2C2%2C3%2C4%2C5%2C7%29%29