Solve for X : 9x+2 = 720 + 9x - Mathematics

Solve for x : 9^x+2= 720 + 9^x

Sum

9^x+2= 720 + 9^x⇒ 9^x+2 - 9^x = 720
⇒ 9^x (9² - 1) = 720
⇒ 9^x (81 - 1) = 720
⇒ 9^x (80) = 720
⇒ 9^x = 9
⇒ 9^x = 9¹⇒ x = 1

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Solving Exponential Equations

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Chapter 7: Indices (Exponents) - Exercise 7 (B) [Page 101]

Chapter 7 Indices (Exponents)
Exercise 7 (B) | Q 14.6 | Page 101

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