SOLUTION: 1. solve using cramers rule 2x+3y=20 3x-2y=17

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Question 1192172: 1. solve using cramers rule
2x+3y=20
3x-2y=17
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
2x%2B3y=20
3x-2y=17


Your matrix
matrix%282%2C3%2C%0D%0A2%2C%093%2C%0920%2C%0D%0A3%2C%09-2%2C%0917%29

Write down the main matrix and find its determinant:

matrix%282%2C2%2C%0D%0A2%2C%093%2C%0D%0A3%2C%09-2%29

Δ =2%28-2%29-3%2A3=+-13

Replace the 1st column of the main matrix with the solution vector and find its determinant:

matrix%282%2C2%2C%0D%0A20%2C%093%2C%0D%0A17%2C%09-2%29

Δ1 = -91

Replace the 2nd column of the main matrix with the solution vector and find its determinant:

matrix%282%2C2%2C%0D%0A2%2C%0920%2C%0D%0A3%2C%0917%29

Δ2 =+-26

x+= Δ1 / Δ =+%28-91%29+%2F+%28-13%29+=+7
y = Δ2 / Δ =+%28-26%29+%2F+%28-13%29+=+2