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1 vote
Solve open parentheses square root of 7 close parentheses to the 6 x power = 49x−6.

x = negative 21 over 2
x = −6
x = negative 6 over 5
x = −12

User Jeryl
by
6.7k points

2 Answers

2 votes
The equation is not setup properly, possibly it is your teacher's fault.

From external research, I would say the answer is x = -12.
User Sharday
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6.2k points
4 votes

Answer:

Option D is correct.

x = -12

Explanation:

Solve:
(√(7))^(6x) = 49^(x-6)

We can write 49 as:


49 = 7 \cdot 7 = 7^2

using exponent rules:


\sqrt[n]{a^m}=a^{(m)/(n)}


(a^m)^n = a^(mn)

Apply this rules on the given equation:


((7)^{(1)/(2)})^(6x) = (7^2)^(x-6)


7^{(6x)/(2)} = 7^(2(x-6))

Simplify:


7^(3x) =7^(2x-12)

On comparing both sides we get;


3x = 2x-12

Subtract 2x from both sides we get;

x = -12

Therefore, the value of x is -12

User Gjert
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5.9k points