Among many other formulas, the area of a triangle is

where B is the angle between sides a and c.

Answer: 92.05 sq cm, first choice
Bonus. Here's a formula for the area S of a triangle your teacher doesn't know:

Answer:
X= 9/2
Alternative form
x=4 1/2, x=4.5
Step-by-step explanation:
*= Multiply
1. log (little 10 under) (2)*(3x-1)= log (little 10 under) (2)*(x+8)
2. then divide both side by log (little 10 under (2))
3. 3x-1=x+8
4. move variable to the left side and change its sign
5. 3x-x-1=8
6. then move constant to the right side and change its sign
7. 3x-x=8+1
8. collect like terms
9. 2x=8+1
10. add 8+1
11. 2x=9
12. then divide both sides by 2
13. 2/2 9/2
14. 2/2 cancels out so x=9/2 is the answer
Answer:
Option a.
Step-by-step explanation:
By looking at the options, we can assume that the function y(x) is something like:


such that, y(0) = √4 = 2, as expected.
Now, we want to have:

replacing y' and y we get:

Now we can try to solve this for "a".

If we multiply both sides by y(x), we get:


We can remove the x factor in both numerators if we divide both sides by x, so we get:

Now we just need to isolate "a"


Now we can subtract a*x^2 in both sides to get:

Then the solution is:

The correct option is option a.