Help please?thank u

BC ≈ 21 units

Step-by-step explanation:

This problem cannot use the Pythagorean theorem as it is not a right triangle. However, you can use the law of cosines, which states that the formula works for any triangle (given that a, b and c are sides of a triangle and the angle c is opposite vertices C)

In this case, a and b can be replaced with 12 and 15 respectively, and angle c is 105 degrees.

the cosine of 105 degrees is about -0.25882 rounded to the 5th decimal place

After the difference, you should end up with BC^2 and by taking its root, you should end up with about 21.49825 or rounded to the nearest whole number, 21.

Hope this helps : )

c is the answer

step-by-step explanation:

ratio is 2 : 9

the answer is three

13.5 : 3