Answer:
900
Step-by-step explanation:
1 + sec^2(x)sin^2(x) = sec^2(x)
This becomes
1+tan^2(x) = sec^2(x) which is an identity
You could
1 + sin^2(x)/cos^2(x) = sec^2(x)
then
cos^2(x) + sin^2(x) = cos^2(x)sec^2(x)
1 = 1
156.25 because a square has 4 sides so it would be 625/4 which equals to the answer 156.25