SOLUTION: using cramer's rules ,solve the following system of linear epuations x+2y=7 3x-4y=-9

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Question 470933: using cramer's rules ,solve the following system of linear epuations
x+2y=7
3x-4y=-9
Answer by Tatiana_Stebko(1539) About Me  (Show Source):
You can put this solution on YOUR website!
using Cramer's rules x=det%28A1%29%2Fdet%28A%29, y=det%28A2%29%2Fdet%28A%29,
det%28A%29=abs%28matrix%282%2C2%2C1%2C2%2C3%2C-4%29%29=1%2A%28-4%29-2%2A3=-10
det%28A1%29=abs%28matrix%282%2C2%2C7%2C2%2C-9%2C-4%29%29=7%2A%28-4%29-2%2A%28-9%29=-10
det%28A2%29=abs%28matrix%282%2C2%2C1%2C7%2C3%2C-9%29%29=1%2A%28-9%29-7%2A3=-30
x=%28-10%29%2F%28-10%29=1, y=%28-30%29%2F%28-10%29=3,
Answer (1,3)