19) 38.75 miles
62*.625(aka 5/8) =38.75
20) x = -4 / x = +4
X^2 + 1 = 17 >subtract 1 from both sides.>X^2 = 16. both -4 and +4 squared equal +16.
21)
With 6 pints for 1.92, each pint is worth .32
With 4 pints for 1.26, each pint is worth .315
The smaller bottle has a smaller pint to cost ratio allowing for same item but at a smaller cost. If the 4 pints are bought, one saves a total of .02.
-0.80 because it is .10 for every dash
Start with
![-3|2x+6|=-12](https://tex.z-dn.net/?f=-3%7C2x%2B6%7C%3D-12)
Divide both sides by -3
![|2x+6|=4](https://tex.z-dn.net/?f=%7C2x%2B6%7C%3D4)
If the absolute value of a number is 4, that number can either be 4 or -4: we have the two solutions
![2x+6=4 \iff 2x=-2 \iff x=-1](https://tex.z-dn.net/?f=2x%2B6%3D4%20%5Ciff%202x%3D-2%20%5Ciff%20x%3D-1)
![2x+6=-4 \iff 2x=-10 \iff x=-5](https://tex.z-dn.net/?f=2x%2B6%3D-4%20%5Ciff%202x%3D-10%20%5Ciff%20x%3D-5)
C.<span>She used an incorrect formula. The formula should be the change in </span>y<span>-values with respect to the change in the </span>x<span>-values.
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The average speed of the delivery truck would be 136.5