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CEMC Fermat

Algebra Difficulty 2.0 Junior Find the answer

The product of the roots of the equation (x−4)(x−2)+(x−2)(x−6)=0(x-4)(x-2)+(x-2)(x-6)=0 is

A number or a short expression. Fractions can be typed as 3/2, and spacing doesn't matter.

Solution

Since the two terms have a common factor, then we factor and obtain (x−2)((x−4)+(x−6))=0(x-2)((x-4)+(x-6))=0. This gives (x−2)(2x−10)=0(x-2)(2x-10)=0. Therefore, x−2=0x-2=0 (which gives x=2x=2) or 2x−10=02x-10=0 (which gives x=5x=5). Therefore, the two roots of the equation are x=2x=2 and x=5x=5. Their product is 10.

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