Answer:
9.) 
10.) 
11.)
minutes of calling would make the two plans equal.
12.) Company B.
Step-by-step explanation:
Let <em>t</em> equal the total cost, and <em>m,</em> minutes.
Set up your models for questions 9 & 10 like this:
<em>total cost = (cost per minute)# of minutes + monthly fee</em>
Substitute your values for #9:

Substitute your values for #10:

__
To find how many minutes of calling would result in an equal total cost, we have to set the two models we just got equal to each other.

Let's subtract
from both sides of the equation:

Subtract
from both sides of the equation:

Divide by the coefficient of
, in this case: 

__
Let's substitute
minutes into both of our original models from questions 9 & 10 to see which one the person should choose (the cheaper one).
Company A:

Multiply.

Add.

Company B:

Multiply.

Add.

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Angle 4 would also be 135. the two on the top would add to 180, making a whole circle altogether that equals 360. so, you would do 180-135 = 45. angle 5 is 45. angle 7 would also be 135 because angle 4 and 7 are vertical angles.
Answer: 5, 8
<u>Step-by-step explanation:</u>
The difference between 3 times a number and -8 is BETWEEN 23 and 32
Note: "difference" means subtraction --> 3x - (-8) --> 3x + 8
23 < 3x + 8 < 32
15 < 3x < 24 <em> subtracted 8 from all 3 sides</em>
--> 5 < x < 8 <em>divided 3 from all 3 sides</em>