Answer :

To solve the equation [tex]\( 5^{-4x} = 25^{1-x} \)[/tex], we'll start by rewriting everything with a common base. Notice that [tex]\(25\)[/tex] can be expressed as a power of [tex]\(5\)[/tex].

Since [tex]\(25 = 5^2\)[/tex], we can rewrite the equation as:
[tex]\[ 5^{-4x} = (5^2)^{1-x} \][/tex]

Next, apply the power of a power property, [tex]\((a^b)^c = a^{bc}\)[/tex], to the right-hand side:
[tex]\[ (5^2)^{1-x} = 5^{2(1-x)} \][/tex]

This simplifies to:
[tex]\[ 5^{-4x} = 5^{2 - 2x} \][/tex]

Now that both sides of the equation have the same base, we can set their exponents equal to each other:
[tex]\[ -4x = 2 - 2x \][/tex]

To solve for [tex]\( x \)[/tex], first isolate the terms involving [tex]\( x \)[/tex] on one side of the equation. Add [tex]\( 2x \)[/tex] to both sides:
[tex]\[ -4x + 2x = 2 - 2x + 2x \][/tex]

Simplify:
[tex]\[ -2x = 2 \][/tex]

Now, divide both sides by [tex]\(-2\)[/tex]:
[tex]\[ x = \frac{2}{-2} \][/tex]

This simplifies to:
[tex]\[ x = -1 \][/tex]

Therefore, the solution to the equation [tex]\( 5^{-4x} = 25^{1-x} \)[/tex] is:
[tex]\[ x = -1 \][/tex]