a triangle with a 18"base.What is the maximum length to use 180in squared?

Length of what? The altitude? If the AREA is 180 in^2, the altitude must be 20 inches.

(1/2)*18*x = 180
Solve for x.

Lupe earns $100 per day plus 8% of her sales in commissions at her current job. Another company offers to pay her $400 per day and no commission. Use the inequalities to determine the dollar amount of sales Lupe must make to earn more money at her current job

To find the maximum length of a triangle with a given base length that can enclose a certain area, we can use the formula for the area of a triangle:

Area = (1/2) * base * height

In this case, we know the base length is 18 inches, and the area is given as 180 square inches. We need to find the maximum height that will allow us to achieve the given area.

Substituting the known values into the formula, we have:

180 = (1/2) * 18 * height

Simplifying the equation, we get:

180 = 9 * height

Dividing both sides by 9, we find:

height = 20

Therefore, the maximum height for a triangle with a base of 18 inches and an area of 180 square inches is 20 inches.