Assuming f(x) is the cost and X is the number of months.
f(x)=2x+40
I don’t know the answer but I can tell you how to do it subtract starting value minus final value divide that amount by the absolute value of the starting value multiply by 100 to get percent decrease if the percentage is negative it means there was an increase not a decrease
Answer:
A
Step-by-step explanation:
Answer:
x=-4
Step-by-step explanation:
(x+4) ^ (1/3) + (2x+8) ^ (1/3) = 0
Subtract (x+4) ^ (1/3) from each side
(x+4) ^ (1/3) - (x+4) ^ (1/3)+ (2x+8) ^ (1/3) = -(x+4) ^ (1/3)
(2x+8) ^ (1/3) = -(x+4) ^ (1/3)
Cube each side
(2x+8) ^ (1/3) ^3= -(x+4) ^ (1/3)^3
2x+8 = -(x+4)
Distribute the negative sign
2x+8 = -x -4
Add x to each side
2x+8 +x =-x+x-4
3x+8 = -4
Subtract 8 from each side
3x+8-8 =-4-8
3x =-12
Divide by 3
3x/3 = -12/3
x = -4
Answer:
30 mph
Step-by-step explanation:
time = distance/speed
If x represents Jane's speed along the summit then her total exploration time is ...
12/x + 40/(x -5) = 2 . . . . . hours
Multiplying by (x)(x -5), we get ...
12(x -5) +40(x) = 2(x)(x -5)
Dividing by 2 and subtracting the left side gives ...
x^2 -31x +30 = 0
(x -30)(x -1) = 0 . . . . . factor
Solutions are x = 30 and x = 1, values of x that make the factors zero. A speed of 1 mph makes no sense in this problem, so ...
Jane's speed along the summit was 30 mph.
