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Algebra Difficulty 2.0 Junior Find the answer

If 3x=5 3^x = 5 , what is the value of 3x+2 3^{x+2} ?

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

Solution

Using exponent laws, 3x+2=3x⋅32=3x⋅9 3^{x+2} = 3^x \cdot 3^2 = 3^x \cdot 9 . Since 3x=5 3^x = 5 , then 3x+2=3x⋅9=5⋅9=45 3^{x+2} = 3^x \cdot 9 = 5 \cdot 9 = 45 .

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