Answer:
f(x) = (x - 10) (x + 10)
Step-by-step explanation:
The equation looks like the difference of squares so 5 and 20 are out
-10 x -10 = 100
-10 x 10 = - 100
so (x - 10) (x + 10)
Cot= cos/sin
<=> cot= [(✔️13^2-5^2)/13]/(5/13)
<=> cot= (12/13)/(5/13)
<=> cot= 12/5