1. 2.
3
Draw a double number line diagram that represents a ratio in the situation.
Write a sentence that describes this situation and that uses the word per.
There are two ears per cat. There are 4 paws per cat. There are 1 tail per cat

this is a direct variation proportion. y = kx

y is the total amount due, k is the constant of variation, and x is the number of texts sent.

plug in the 3.20 and the 16 to solve for the "k". this is the constant of proportionality. it is the value that will not change.

3.20 = k(16). solving you get $.20 per text.

the equation would then be y = .20x

if your equation is in the form ax2 + bx + c, you can find the maximum by using the equation:

max = c - (b2 / 4a).

the first step is to determine whether your equation gives a maximum or minimum.

-x2 + 4x - 2.     thats an example hope it