Determine the value of variables a, b, and c that make each equation true.

What is the value of a in this equation?
(xa)6 = StartFraction 1 Over x Superscript 30 EndFraction
a =
What is the value of b in this equation?
(x–7)–4 = xb
b =
What is the value of c in this equation?
(x–2)c = x22
c =

1 answer

To determine the values of \( a \), \( b \), and \( c \) from the given equations, let's solve each equation one by one.

1. Determine the value of \( a \) in the equation \((xa)^6 = \frac{1}{x^{30}}\)

First, we rewrite the left side of the equation:

\[ (xa)^6 = x^6 a^6 \]

Now, set the two sides equal to each other:

\[ x^6 a^6 = \frac{1}{x^{30}} \]

Recall that:

\[ \frac{1}{x^{30}} = x^{-30} \]

So we have:

\[ x^6 a^6 = x^{-30} \]

This means that the exponents of \( x \) on both sides must be equal:

\[ 6 + \log_x(a^6) = -30 \]

From \( x^6 a^6 = x^{-30} \), we can also notice that \( a^6 \) itself must have a term corresponding to \( x^{-30} \) so we only set:

\[ 6 + \log_x(a^6) = -30 \]

Thus,

\[ 6 = -30 \Rightarrow a^6 = x^{-36} \]

Therefore, from \( 6 + log_x(a^6) = -30 \), we re-focus and simply rearrange to:

Hence, \( 6 + \log_x(a) = -30 \)

This implies:

\[ \log_x(a) = -30 - 6 = -36 \] Thus, we can write:

\[ a = x^{-36} \]

Thus, since we need only the constant value of the exponent:

\[ a = -36 \]

2. Determine the value of \( b \) in the equation \((x^{-7})^{-4} = x^b\)

Apply the power of a power property:

\[ (x^{-7})^{-4} = x^{-7 \cdot -4} = x^{28} \]

Now, equate the exponents:

\[ b = 28 \]

3. Determine the value of \( c \) in the equation \((x^{-2})^c = x^{22}\)

Again, applying the power of a power property, we can rewrite the left-hand side:

\[ (x^{-2})^c = x^{-2c} \]

Now, set the exponents equal:

\[ -2c = 22 \]

To solve for \( c \), divide both sides by -2:

\[ c = \frac{22}{-2} = -11 \]

Summary of Values

  • \( a = -36 \)
  • \( b = 28 \)
  • \( c = -11 \)

Thus,

\[ \boxed{a = -36}, \quad \boxed{b = 28}, \quad \boxed{c = -11} \]