3. at a 25% off everything sale, bill purchased a new shirt. if c represents the original cost, write an expression for the sale price of the shirt.

0.75*C  

Step-by-step explanation:

Original cost is 100%, 25%sale means that Bill payed only 75% of original cost.

Each number can be written as a decimal, as a fraction, or as a percent.

75%=0.75=3/4

salePrice = 0.75C

or salePrice = (3/4)*C

pentagon

step-by-step explanation:

the coordinates   a(5, -2), b(3,-1),c(-4,-4) d(-3,8) and e(-1,4) forms the vertices of the polygon when they are connected in order.

in order to classify that which polygon is it with the given coordinates, first count the number of vertices and then count the number of sides it can make with these vertices.

since, the given coordinates have five vertices, therefore, it will make five sides. moreover, pentagon is regular in nature therefore it will be convex.

now, a polygon with five sides is known as pentagon, therefore, the given polygon is the pentagon.