Y + -4 = 9 (this means y plus negative 4 equals 9)
y -4 = 9
+4 +4
y = 13
Answer:
If you add any number to itself, the result is divisible by 2.
so two fellows did all the carpeting in 10 days.
now, how long did "1" fellow work only? well, it worked for 10 days.
how long did the other fellow work for? well, it was working alongside the first one, and it was there for also 10 days.
so the two guys working together, really did 10+10 = 20 "days worth of work". So that the whole carpeting job can be done in 20 "days worth of work".
now if we want to finish it in 4 days, 20 ÷ 4 = 5.
so if we hire 5 guys, since each one will do 4 days worth, 5*4 = 20 <- the whole job.
To solve this, you have to know that the first derivative of a function is its slope. When an interval is increasing, it has a positive slope. Thus, we are trying to solve for when the first derivative of a function is positive/negative.
f(x)=2x^3+6x^2-18x+2
f'(x)=6x^2+12x-18
f'(x)=6(x^2+2x-3)
f'(x)=6(x+3)(x-1)
So the zeroes of f'(x) are at x=1, x=-3
Because there is no multiplicity, when the function passes a zero, he y value is changing signs.
Since f'(0)=-18, intervals -3<x<1 is decreasing(because -3<0<1)
Thus, every other portion of the graph is increasing.
Therefore, you get:
Increasing: (negative infinite, -3), (1, infinite)
Decreasing:(-3,1)
If n = number of hours and the equation is 174 + 58n then the answer is 3 hours
174 = 58n
÷ 58
3 = n