The equation you can use is x + 3x = 428 with x as the number of cheeseburgers and 3x the number of hamburgers
you solve for x and get 4x= 428 and x=107
so 321 hamburgers were sold that day.
Answer:
Draw a diagram. Then use tan(x) to find the remainder height of the taller building.
Step-by-step explanation:
Answer:

Step-by-step explanation:
Given
Shapes: Cube and Cone
Required
Determine the volume
First we calculate the volume of the cube

Where
l = side length = 5.1


Next, calculate the volume of the cone using:

Where
h = 5.1



So, we have:





The volume of the figure is:




The given equations are

(1)

(2)
When t=0, obtain

Obtain derivatives of (1) and find x'(0).
x' (t+1) + x - 4√x - 4t*[(1/2)*1/√x = 0
x' (t+1) + x - 4√x -27/√x = 0
When t=0, obtain
x'(0) + x(0) - 4√x(0) = 0
x'(0) + 9 - 4*3 = 0
x'(0) = 3
Here, x' means

.
Obtain the derivative of (2) and find y'(0).
2y' + 4*(3/2)*(√y)*(y') = 3t² + 1
When t=0, obtain
2y'(0) +6√y(0) * y'(0) = 1
2y'(0) = 1
y'(0) = 1/2.
Here, y' means

.
Because

, obtain

Answer:
The slope of the curve at t=0 is 1/6.
Answer:
He should pay $2,790.7.
Step-by-step explanation:
This is a simple interest problem.
The simple interest formula is given by:

In which E is the amount of interest earned, P is the principal(the initial amount of money), I is the interest rate(yearly, as a decimal) and t is the time, in years.
After t years, the total amount of money is:

In this question:
Rate of 10%, so I = 0.1.
9 months, so 
How much should he pay for a note that will be worth $3,000 in 9 months?
We have to find P for which T = 3000. So



Then





He should pay $2,790.7.