Solve for x and y: ax + by = a-b and bx - ay = a+b. – Algebra

Algebrahard · Past Paper

Solve for x and y: ax + by = a-b and bx - ay = a+b.

Ax=1, y=-1

Bx=-1, y=1

Cx=1, y=1

Dx=0, y=0

✓ Correct Answer: A — x=1, y=-1

Multiply first by a and second by b, then add: (a^2+b^2)x = a^2-ab+ab+b^2 = a^2+b^2. So x=1. Substitute x=1: a+by=a-b -> by=-b -> y=-1.

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