Select the correct answer.

What is the solution to this equation?

[tex]\[ \left(\frac{1}{4}\right)^{x+1}=32 \][/tex]

A. [tex]\(-\frac{7}{2}\)[/tex]
B. [tex]\(\frac{3}{2}\)[/tex]
C. 2
D. -2



Answer :

To solve the equation [tex]\(\left(\frac{1}{4}\right)^{x+1} = 32\)[/tex], let's go through the steps systematically:

1. Express 32 as a power of 4:

We know that [tex]\(32 = 2^5\)[/tex]. However, considering we want to express [tex]\(32\)[/tex] in terms of base [tex]\(4\)[/tex], we note that:
[tex]\[ 32 = 4^{\frac{5}{2}} \][/tex]
This is because [tex]\(4^{1.5} = 2^3\)[/tex], and further exponentiation of 2 leads to the power we need.

2. Rewrite the given equation:

The equation is:
[tex]\[ \left(\frac{1}{4}\right)^{x+1} = 32 \][/tex]
Notice that [tex]\(\frac{1}{4}\)[/tex] can be rewritten as [tex]\(4^{-1}\)[/tex]. Thus:
[tex]\[ \left(4^{-1}\right)^{x+1} = 32 \][/tex]
Simplify the left-hand side to get:
[tex]\[ 4^{-(x+1)} = 32 \][/tex]
Using our earlier transformation for 32:
[tex]\[ 4^{-(x+1)} = 4^{\frac{5}{2}} \][/tex]

3. Set the exponents equal to each other:

Since we now have the same base, we can set the exponents equal:
[tex]\[ -(x+1) = \frac{5}{2} \][/tex]

4. Solve for [tex]\(x\)[/tex]:

Simplify the equation:
[tex]\[ -(x+1) = \frac{5}{2} \][/tex]
[tex]\[ x + 1 = -\frac{5}{2} \][/tex]
Subtract 1 from both sides:
[tex]\[ x = -\frac{5}{2} - 1 \][/tex]
Convert 1 to a fraction format to combine:
[tex]\[ x = -\frac{5}{2} - \frac{2}{2} \][/tex]
[tex]\[ x = -\frac{7}{2} \][/tex]

Thus, the solution to the equation [tex]\(\left(\frac{1}{4}\right)^{x+1} = 32\)[/tex] is

[tex]\[ \boxed{-\frac{7}{2}} \][/tex]

Therefore, the correct answer is [tex]\(A. -\frac{7}{2}\)[/tex].