Answer:
C is the correct answer.
Step-by-step explanation:
<span>x-axis: hours in increments of 1; y-axis: miles in increments of 5
You always want the constant numbers such as time on the x-axis
And since your y values are all large numbers and multiples of 5, it makes sense to use increments of 5</span>
bearing in mind that an absolute value expression is in effect a piece-wise expression, because it has a ± version.
![\bf 3|x|+7=28\implies 3|x|=21\implies |x|=\cfrac{21}{3}\implies |x|=7\implies \begin{cases} +(x)=7\\ -(x)=7 \end{cases} \\\\[-0.35em] ~\dotfill\\\\ +(x)=7\implies \boxed{x=7}~\hfill -x=7\implies \boxed{x=-7}](https://tex.z-dn.net/?f=%20%5Cbf%203%7Cx%7C%2B7%3D28%5Cimplies%203%7Cx%7C%3D21%5Cimplies%20%7Cx%7C%3D%5Ccfrac%7B21%7D%7B3%7D%5Cimplies%20%7Cx%7C%3D7%5Cimplies%20%20%5Cbegin%7Bcases%7D%20%2B%28x%29%3D7%5C%5C%20-%28x%29%3D7%20%5Cend%7Bcases%7D%20%5C%5C%5C%5C%5B-0.35em%5D%20~%5Cdotfill%5C%5C%5C%5C%20%2B%28x%29%3D7%5Cimplies%20%5Cboxed%7Bx%3D7%7D~%5Chfill%20%20-x%3D7%5Cimplies%20%5Cboxed%7Bx%3D-7%7D%20)
Explanation:
Find the two closest square numbers to 1659.
40*40=1600
41*41=1681
Decide much closer to either 1600 or 1681 is 1659.
If it is exactly halfway between the two numbers, the square root is 40.5.
If it is closer to 1600, the sq rt decimal is between 1 and 4.
If it is closer to 1681, the sq rt decimal is between 6 and 9.
This can be expanded through the tangent angle addition formula:
tan(α+β)=tanα+tanβ1−tan -α + tanβ
Thus,tan(x+y)=tanx+tany1−tan x tany
Hope it helps you
