Answer:
the first one
Step-by-step explanation:
In the other 2 i can see the x repeats itself meaning it isn't a function.
we have that
the total cost is

In this equation the term 30h represent the cost due to h hours at at unit of 30
and the term 0.040(30h) is equal to calculate the 4% of (30h)
so
in this problem the tax rate is equal to 4%
therefore
<u>the answer is</u>
The term 0.040(30h) represents the amount of tax she must pay
Answer:
Step-by-step explanation:
Perimeter is
P = 2L + 2W. We are given the perimeter as 180 feet, so
180 = 2L + 2W. Solve this for either L or W. I chose W, no reason...
180 - 2L = 2W so
90 - L = W Hold that thought. We'll come back to it in a minute.
Area is
A = LW. We are given the area as 1800 square feet, so
1800 = LW. Sub in 90 - L for W:
1800 = L(90 - L). Distribute to get a quadratic:

Get everything on one side and solve for the length by factoring:

Factor this however you like to factor quadratics, to get the length of
L = 30 and L = 60. First off, the length is longer than the width in general, so if we want to solve for the width, plug in 60 as L in the equation in bold print:
90 - 60 = W and
30 = W
So L = 60 and W = 30
8/8 hours because he can play for a longer amount of time
Answer:
-7/2
Step-by-step explanation:
The slope of a line can be defined as:
, which can be more formally calculated as:
, where it's essentially the same thing, except the rise/run is being calculated with two points (which you already need)
So let's just say: 
Plugging the values into the equation we get: 
You can also just look at the graph and see that from point 1 to point 2, it "rised" -7 units, and "ran" 2 units.
Notice how the "rise" is negative? That just means it went down.