1. The problem statement, all variables and given/known data Now, ignore the lengths given in the photo. Height (y) = .640 meters Length (z) = 1.18 meters Base (x) = .320 meters Magnetic Field (B) = 3.5 Teslas in the +X direction 2. Relevant equations The problem is to find the magnetic flux through the surface of the prism that is the hypotenuse (side aedf). So, the equation for this should be Flux = BAcos(theta) 3. The attempt at a solution Well, working out the problem, I figured out the length of the hypotenuse is 1.22m because of pythagorean theorem. So, B*A is simply (1.22)(.640)(3.5T)=2.7328 Now, theta is the angle that is between the magnetic field and the orthogonal of the surface itself. This angle should be the same as the angle between the base of the triangle and the hypotenuse. So this ratio is (1.18/1.22). So the flux should be 2.7328 * (1.18/1.22) = 2.6432 Wb But the answer keeps spitting out as wrong! What did I do wrong here?