4.3
4=ones
.3= hundredths
0=tenths
Hope I helped:P
Part A)
The table doesn't represent y as a function of x.
Why? <span>One reason is that 1 or 3 is the first element in more than one ordered pair.
Part B)
f(x) = 10x + 20
f(120)= 10*120 + 20 = 1200 + 20 = 1220
</span><span>f(120) represents cost of boating for 120 hours.</span><span>
</span>
For this case we have that by definition, the equation of a line in the slope-intersection form is given by:

Where:
m: It's the slope
b: It is the cut-off point with the y axis
On the other hand we have that if two lines are perpendicular, then the product of their slopes is -1. So:

The given line is:

So we have:

We find 

So, a line perpendicular to the one given is of the form:

We substitute the given point to find "b":

Finally we have:

In point-slope form we have:

ANswer:

Step-by-step explanation:
11. shape 1 => A = ½×17×10=85m²
shape 2=> A = 17×9 =153 m²
total area = 238 m²
12. shape 1 => A = 7×3= 21 m²
shape 2=> A = 3×2 = 6 m²
total area = 27 m²