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Algebra Difficulty 2.2 Junior Find the answer

If x=2 x=2 and v=3x v=3x , what is the value of (2v5)(2x5)(2v-5)-(2x-5)?

A number or a short expression. Spacing and $ signs are ignored.

Solution

Since v=3x v=3x and x=2 x=2 , then v=32=6 v=3 \cdot 2=6 . Therefore, (2v5)(2x5)=(265)(225)=7(1)=8(2v-5)-(2x-5)=(2 \cdot 6-5)-(2 \cdot 2-5)=7-(-1)=8.

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