The answer is: 2a^4 - 3a^2 b - 5b^2
Answer:

Step-by-step explanation:
using the cosine ratio;

From the question, the side of the right angle triangle that is adjacent to the measured <a,(i.e BAC) is AC=24 and the hypotenuse is AB=25
This implies that,

To find the common ratio, u take ur 2nd term, and divide it by ur 1st term
(-1/6) / (5/12) =
-1/6 * 12/5 =
- 2/5 <== ur common ratio
Plog in to y=ax+b and u will find a b