Answer:
-17 degrees
Step-by-step explanation:
Given that:
Initial temperature = 2 degrees
Final temperature = -15 degrees
To Determine:
The change in temperature.
Solution:
First of all, let us have a look at the method for calculating the change in any quantity.
Let the initial quantity = 
Let the final quantity = 
Change in quantity = Final quantity - Initial quantity = 
Here, we are given the quantity as temperature.
where
degrees and
degrees
Therefore, the change in temperature = -15 - 2 =
<em>degrees</em>
Rearrange the equation into slope intercept form
7x+3y=18
3y=-7x+18
y=-7x/3+18/3 so the slope of the reference line is -7/3
To be perpendicular to this line the slope must be the negative reciprocal of this...mathematically m1*m2=-1. So the slope of our perpendicular line is:
-7m/3=-1
-7m=-3
m=3/7 so our line so far is:
y=3x/7+b, using point (6,8) we can solve for b, the y-intercept
8=3(6)/7+b
8=18/7+b
56/7-18/7=b
38/7=b so our line is:
y=3x/7+38/7 or if you prefer
y=(3x+38)/7
If he is selling shovels at $19 each, the answer of $153 would be incorrect. If you take $153 and divide that by 8 (shovels) you will get each shovel being a price of $19.125 each.
The overall answer of $153 could be reasonable but the overall price from selling 8 shovels will actually be $154 not $153.
I think it’s the third one hope this helps