Answer:

Step-by-step explanation:
We are required to solve for c in the equation: 
Step 1: Collect like terms

Step 2: Find the Lowest Common Multiple of the denominators
LCM of 8 and 5 is 40
Step 3: Multiply all through by 40

Step 4: Simplify
40c=32-5
40c=27
Step 5: Divide both sides by 40 and simplify if possible.

X^2
You subtract exponents when dividing exponents
Answer:
<em>y=0.10(t)+0.25 </em>
<em>27 minutes and 30 seconds </em>
Step-by-step explanation:
We know that you start with 25 cents as a service fee, this is for making the call. For each minute you talk, 10 cents are added. Multiply the number of minutes spent by 10 cents a minute for the cost based on the call. Then add the 25 cents service fee.
If you talked for 5 minutes:
y=0.10(5)+0.25
y=0.50+0.25
y=0.75
75 Cents
For three dollars, you would plug in 3 for y
3.00=0.10(t)+0.25
-0.25 -0.25
2.75=0.10(t)
divide both sides by 0.10 to get
27.5=t
You can talk for 27 minutes and 30 seconds
27 minutes
<u>Hope this helps :-)</u>
To determine if it is a function or not, you can not have a vertical line drawn down the graph touch 2 of the graphed points. That means that you can not have 2 points with the same x value and different Y value. The first set of points satisfies this and is your answer. Hope that helps.