Answer:
i don't know, -75 is the slope
Step-by-step explanation:
Let's start with what we know:

And we are trying to put it into this form:

Here is what it would look like:

You can check you work by using the FOIL method (first, outer, inner, last)
Let the number of text messages be represented by X.
Then the total cost of David's cell phone adds up to

Since the total cost of David's phone equals $91.40, we get the following equation.

Subtract 50 on both sides

Divide both sides by 0.45

Therefore David has send 92 text messages.
Answer:
4ab and 3ab
Step-by-step explanation:
4<em>ab</em> and 3<em>ab</em> because they have the same variables <em>a</em> and <em>b</em>
You multiply -9 and -6 to solve for e.
e/-9 = -6
e = -9*-6
e = 54
Hope this helps :)