Answer:

Step-by-step explanation:
The diagram shows right triangle with hypotenuse of 15 units and angle of 30°. This angle is opposite to the leg with length of x units.
In the right triangle, the leg opposite to the 30° angle is half of the hypotenuse, so

<span>Bob should by the 25cm cake for 18.75 each. He will need to buy 3 of these cakes in order to feed 57 guests. The total cost would be 56.25. If he were to buy the 20cm cake, he would need to purchase 5 cakes for a total of 67.50.</span>
The total revenue that is gained from the sales of the cakes is determined by multiplying the number of cakes by the price. If we let x be the number of $1 that should be deducted from the price and y be the total revenue,
y = (25 - x)(100 + 5x)
Simplifying,
y = 2500 + 25x - 5x²
We get the value of x that will give us the maximum revenue by differentiating the equation and equating the differential to zero.
dy/dx = 0 = 25 - 10x
The value of x is 2.5.
The price of the cake should be 25 - 2.5 = 22.5.
Thus, the price of the cake that will give the maximum potential revenue is $22.5.
Bryan spends T=15x
320 divided by 15 is and average of $21 per week
The given expression can be simplified in many ways by grouping like terms. The simplest form is obtained by factoring out a²b which gives us the following expression.
a²b(7 + 10b +14b²)