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31 votes
31 votes
Solve for the exponential for x

Solve for the exponential for x-example-1
User Viator
by
2.4k points

2 Answers

24 votes
24 votes

Answer:

x = 1

Explanation:

Using Definition of Logarithm

7 ^(4x−6) = 1/49

​Use the rules of exponents and logarithms to solve the equation.

7 ^(4x−6) = 1/49

​Take the logarithm of both sides of the equation.

log(7^4x-6) = log(1/49)

The logarithm of a number raised to a power is the power times the logarithm of the number.

(4x-6)log(7) = log(1/49)

Divide both sides by log(7).

4x-6 = log(1/49)/log(7)

​By the change-of-base formula log(a)/log(b) = log(small b under) (a).

4x-6 = log(small 7 under) (1/49)

Add 6 to both sides of the equation.

4x=−2−(−6)

Divide both sides by 4.

x = 4/4 which is the same as x = 1

User Nimda
by
3.1k points
26 votes
26 votes

Answer:

x = 1

Explanation:


{7}^((4x - 6)) = (1)/(49) \\ \\ \implies {7}^((4x - 6)) = \frac{1}{ {7}^(2) } \\ \\ \implies {7}^((4x - 6)) = {7}^( - 2) \\ \\ \implies \: 4x - 6 = - 2 \\ \\ \implies \: 4x = 6 - 2 \\ \\ \implies \: 4x = 4 \\ \\ \implies \: x = (4)/(4) \\ \\ \implies \: x = 1

User Keshav Lodhi
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2.4k points