A clothing store determines that in order to sell x shirts, the price per shirt should be p(x)=100−x dollars. Getting x shirts from the supplier costs the store C(x)=1,600+20x dollars. If the store’s revenue from selling x shirts is R(x)=x⋅p(x), for what value of x will the store’s cost and revenue be equal?

x= -40

Step-by-step explanation:

Cost

C(x)=1,600+20x

P(x)=100-x

Revenue=x*p(x)

=x*(100-x)

=100x-x^2

Cost=Revenue

1600+20x=100x-x^2

1600+20x-100x+x^2=0

1600-80x+x^2=0

Solve using quadratic formula

Formula where

a = 1, b = 80, and c = 1600

x=−b±√b2−4ac/2a

x=−80±√80^2−4(1)(1600) / 2(1)

x=−80±√6400−6400 / 2

x=−80±√0 / 2

The discriminant b^2−4ac=0

so, there is one real root.

x= −80/2

x= -40

b: |12 – x| ≤ 0.25

step-by-step explanation:      

let x be the possible lengths in inches, of the ribbons jaime cut.

we have been given that jaime is cutting strips of ribbon for a project. he tries to cut each piece to be 12 inches long, but sometimes he cuts it too long or too short by as much as 0.25 inch.  

we can represent this information in an inequality as:

by the definition of absolute value function we will get,

upon combining our inequalities we will get,

therefore, the inequality   describes all the possible lengths (x), in inches, of the ribbons jaime cut.

step-by-step explanation: