Answer:
200 litres
Step-by-step explanation:
let g be gasoline used, d the distance travelled and s the speed, then the equation relating the quantities is
g = kd
← k is the constant of variation
To find k use g = 25, d = 100 and s = 100, then
25 = k × 100 × 
= k × 100 × 10 = 1000k ( divide both sides by 1000 )
0.025 = k
g = 0.025d ← equation of variation
When d = 1000 and s = 64, then
g = 0.025 × 1000 × 
= 0.025 × 1000 × 8 = 200
(1/x) - (2x/(1+x^2)) = 0
Multiply by x(x^2+1)
1(x^2+1)+(−2x)(x)=0x(x2+1)
−x^2+1=0(Simplify both sides of the equation)
−x^2+1−1=0−1(Subtract 1 from both sides)
−x^2=−1
−x^2−1=−1−1(Divide both sides by -1)
x^2=1
x=ñ1(Take square root)
x=1 or x=−1
Answer:
Number of offices to be cleaned to cover the cost of equipment =15
Cost of equipment =$.315 Cost of supplies =$.4 Charge per office =$.25
Number of offices to be cleaned to cover the cost of equipment =x
Then -25x − 4x =315
21x =315
x=315
21=15
Number of offices to be cleaned to cover the cost of equipment =15
