Answer:
The width of the garden bed must be less than or equal to 4 feet.

Explanation:
Given that;
She has 20 feet of boards to make the sides.
The perimeter of the garden bed must not be more than 20 feet

Given;
The length is 6 feet;

To get the inequality for the width w, let us substitute the value of the length into the inequality above and simplify;

Therefore, the width of the garden bed must be less than or equal to 4 feet.
19 * 42 + 19 * 58 =
19(42 + 58) =
19 * 100 =
1900