If 9x+2 = 240 + 9x, then x = A. 0.5 B. 0.2 C. 0.4 D. 0.1

1.	If 9x+2 = 240 + 9x, then x = A. 0.5 B. 0.2 C. 0.4 D. 0.1
Answer» 9 ^{x + 2} = 240 + 9^x 9x × 9² = 240 + 9^x Let 9^x = y 81y = 240 + y 80y = 240 y = \(\frac{240}{80}\) 9^x = 3 3^2x = 3 2x = 1 x = \(\frac{1}{2}\) = 0.5

Answer»

9 ^{x + 2} = 240 + 9^x

9x × 9² = 240 + 9^x

Let 9^x = y

81y = 240 + y

80y = 240

y = \(\frac{240}{80}\)

9^x = 3

3^2x = 3

2x = 1

x = \(\frac{1}{2}\)

= 0.5

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