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Solve 64^x = 16^x-1

Please help I need to find what x equals

User Illeb
by
4.1k points

2 Answers

3 votes

Answer:

x = -1

Explanation:

lhs is 64 to the power of something, while rhs is 16 to the power of something. so x cannot be a positive number.

if you keep x as 0, 64^0 > 16^-1, which means 1 > 1/16. hence x should be lesser than 0.

With -1, 64^-1 = 16^-2, 1/64 = 1/64

User Dkatzel
by
3.5k points
7 votes

Answer:

x= -2

Explanation:

64^x = 16^x-1

64= 4^3 and 16=4^2

4^3x = 4^2(x-1)

so we now cancel the 4 from both sides and equate the powers

3x=2(x-1)

3x=2x-2

we now put all the x on one side

3x-2x=-2

x= -2

User Supratik Majumdar
by
4.8k points