x^2 = 800. Take the square root of each side.
x = √(800) and -√(800)
He makes it up by 1/3=.333%=$75*1.333=$99.98
he then discounts it by 20%=1/5=99.98/5=$19.99
If the original profit is $99.98-$75=$24.98
and then discounted by $19.99
it would be $24.98-$19.99
=
$4.99
Answer:
3 hours and 45 minutes
Step-by-step explanation:
let's assume the tank has a volume of x liters.
let's assume the speed of filling it is x/6 liters per hour for A and x/10 liters per hour for B.
the formula to calculate the time is:
time = volume / speed
If the pumps work together, the total speed is x/6 + x/10, which is 16/60 x
So the time this takes is:
time = x / (16/60 x) = 60/16 hours = 3.75 hours = 3 hours and 45 minutes.
Answer:

Step-by-step explanation:
Multiply the two polynomials by multiplying each term

Answer:
61°C
Step-by-step explanation:
Newton's Law of cooling gives the temperature -time relationship has:
T (t) = 20 + 75 е⁻(t/50)-------------------------------------------------------- (1)
where Time is in minutes (min) & Temperature in degree Celsius (°C)
During the first half hour, t = 30 mins
Substituting into (1)
T = 20 + 75 е⁻(30/50)
= 20 + 75(0.5488)
= 20 + 41.16
= 61.16°C
≈ 61°C