The answer is A,
if you plug in the points of (2,-5) into
y=x-7
-5=2-7
-5=-5
so the equation is true
Answer:
15x + 40 = 115
We set the equation to 115 because the total cost is $115.
We add the "+ 40" because of the $40 to rent the trailer for the day.
The 15x is because it represents the miles per hour (x) times the number of hours.
The number of hours times the charge per mile, plus the $40 to rent it, will equal $115.
Hope this helps!!
2 .............:)
Good luck
Check the picture.
let the length of a side of each of the squares removed be x.
The box formed will have dimensions: 80-2x, 50-2x, x(the height)
So the volume can be expressed as a function of x as follows:
f(x)=(80-2x)(50-2x)x=
![[4000-160x-100x+4 x^{2} ]x=(4 x^{2}-260x+4000)x](https://tex.z-dn.net/?f=%5B4000-160x-100x%2B4%20x%5E%7B2%7D%20%5Dx%3D%284%20x%5E%7B2%7D-260x%2B4000%29x)
so

the solutions of f'(x)=0 gives the inflection points, so the candidates for maxima points,

solving the quadratic equation, either by a calculator, graphing software, or by other algebraic methods as the discriminant formula, we find the solutions
x=10 and x=33.333
plug in f(x) these values to see which greater:

cm cubed

which is negative because (50-66.666)<0
Answer: 18000 cm cubed