
to solve for j first you need to cross multiply;
j × 35 = 42 × 55
35j = 2,310
j = 2,310 ÷ 35 (did the inverse operation)
j = 66
Hope that helps :D
Right ankle is exactly 90 degrees, while obtuse is more than, and acute is less than
Parameterize
by

with
and
. Take a normal vector to
,

which has norm

Then the integral of
over
is

