Answer: B = 100 - a^2
Solution:
Step 1: Substitute all the values that are given in the equation
that would be C = 25 and S = a
Step 2: when substituted the equation would be
B = 4 (25) - (a)^2
B = 100 - a^2 Would be the answer
Note: if there was a numerical value to s then the answer would be a number but since s=a so the answer has variable too.
