Answer: B) $21
Explanation:
Given : Sean spent $38 for shorts.
This was $4 less than twice what he spent for a shirt.
Let x denotes the cost of shirt.
The equation
is set to find the cost of the shirt (x).
To solve the above equation for x , first we add4 on both the sides , we get

Divide both sides by 2 , we get

Thus , the cos of shirt = $21
Hence, Sean spent $21 on the shirt.
∴ The correct option is B) $21