Think of the two pieces together as a single cone of height 19, and its volume.
Then think of only the upper piece as a cone, and find its volume.
The volume of the frustum is the total volume minus the volume of the upper piece.
The volume of a cone is:

Total volume:

Volume of upper cone:

Volume of frustum:
Answer:
5n-9
Step-by-step explanation:
9 = 2(6) - b
9 = 12 - b
-3 = b
The equation a = 100 + 75d represents Maria's account balance.
<u>Step-by-step explanation:</u>
Given that,
- Maria opened a new savings account with an initial deposit of $100.
- She deposits $75 into this savings account every two-weeks.
You need to find the equation to represent Maria's account balance, a after she has completed d deposits.
- Let 'd' be the number of deposits Maria made after the initial deposit.
- Let 'a' be the total account balance after 'd' deposits.
Therefore, the equation for the total account balance can be framed as the sum of the initial deposit and amount deposited after that.
<u>To find the amount that was deposited after the initial deposit :</u>
⇒ $75 × number of times Maria deposited.
⇒ 75 × d
The equation is written as,
⇒ a = 100 + 75d
Hence the equation a = 100 + 75d represents Maria's account balance.