What is the missing exponent that would make this equation TRUE? k to the power of five times k to the power two divided by k to the power of x equals (k to the power of two) to the power of negative two?

x=3
x=1
x=0
x=6
x=11
x=9

1 answer

To solve the equation \( \frac{k^5 \cdot k^2}{k^x} = (k^2)^{-2} \), we can start by simplifying both sides.

Step 1: Simplify the left side

Using the properties of exponents, we know that: \[ k^5 \cdot k^2 = k^{5 + 2} = k^7 \] So the left side can be rewritten as: \[ \frac{k^7}{k^x} = k^{7 - x} \]

Step 2: Simplify the right side

The right side can be simplified using the property \((a^m)^n = a^{mn}\): \[ (k^2)^{-2} = k^{2 \cdot (-2)} = k^{-4} \]

Step 3: Set the simplified left side equal to the simplified right side Now we can set the two sides equal: \[ k^{7 - x} = k^{-4} \]

Since the bases are the same, we can set the exponents equal to each other: \[ 7 - x = -4 \]

Step 4: Solve for \(x\) To find \(x\): \[ 7 + 4 = x \] \[ x = 11 \]

So the missing exponent \(x\) that makes the equation true is:

\[ \boxed{11} \]