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CEMC Fermat

Algebra Difficulty 2.2 Junior Find the answer

If x=2x=2, what is the value of 4x2−3x24x^2 - 3x^2?

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

Solution

Simplifying, 4x2−3x2=x24 x^{2}-3 x^{2}=x^{2}. When x=2x=2, this expression equals 4 . Alternatively, when x=2x=2, we have 4x2−3x2=4⋅22−3⋅22=16−12=44 x^{2}-3 x^{2}=4 \cdot 2^{2}-3 \cdot 2^{2}=16-12=4.

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