How do I do slope-intercept form of a linear equation? I really don’t get it

Rearrange the formula c^2 = a^2 + b^2 for b

Aparking lot is to be 400 feet wide and 370 feet deep. how many standard-sized cars fit in this lot considering a double-loaded (w4) two way traffic set up, an angle of 90° and a sw of 9’ 0’’? (do not consider handicapped parking spaces, and consider 15’ for turning aisles). show your work.

Iwill give ! if m∠a=59 and m∠3=81°, what is m∠b? m∠b= _[blank]_°