Questions: Which pair of expressions below are equivalent?
Answer
8(5k-2) and 40k-16
8k+5k and 13k^2
8(5k) and 13k
k+k+k+k and k^4
Transcript text: Which pair of expressions below are equivalent?
Answer
$8(5 k-2)$ and $40 k-16$
$8 k+5 k$ and $13 k^{2}$
$8(5 k)$ and $13 k$
$k+k+k+k$ and $k^{4}$
Solution
Solution Steps
Step 1: Expand the first expression
Expand \( 8(5k - 2) \) using the distributive property:
\[
8(5k - 2) = 8 \cdot 5k - 8 \cdot 2 = 40k - 16.
\]
This matches the second expression \( 40k - 16 \), so they are equivalent.
Step 2: Simplify the second pair of expressions
Simplify \( 8k + 5k \):
\[
8k + 5k = (8 + 5)k = 13k.
\]
The second expression is \( 13k^2 \), which is not equal to \( 13k \). Therefore, they are not equivalent.
Step 3: Simplify the third pair of expressions
Simplify \( 8(5k) \):
\[
8(5k) = 40k.
\]
The second expression is \( 13k \), which is not equal to \( 40k \). Therefore, they are not equivalent.
Final Answer
The equivalent pair of expressions is \( 8(5k - 2) \) and \( 40k - 16 \). Thus, the final answer is \\(\boxed{8(5k - 2) \text{ and } 40k - 16}\\).