Answer:
d. 690.1 units²
Step-by-step explanation:
1. You can use the Heron's formula to calculate the area of the triangle, which is:

Where:

2. Calculate
:

3. Substitute values into the formula shown above and calculate the area, as following:

4. Therefore, the area is 690.1 units².
Answer:
x=-20
Step-by-step explanation:
Answer:
8.4 dollars
Step-by-step explanation:
The error is in the resolution of the proportion. In fact, the initial proportion is correct:

where x is the total cost. However, the following step of the resolution is wrong. In fact, the correct resolution is the following:
- Multiplying by x on both sides:

- Multiplying by 3.5 no both sides:

And now we can find x:

So, the total cost is 8.4 dollars.
Answer:
1) is 40%
2) is 4,307
3) is 35
I think it's correct you can double-check. I apologize if it's wrong.
Step-by-step explanation: