Angle a and angle b are complementary angles of right triangle abc, cos a = 0.83, and cos b = 0.55. what is sin a + sin b?
a) 0.28
b) 1
c) 0.38
d) 1.38

The perimeter of an equilateral triangle is 4 cm more than the perimeter of a square and the length of a side of the triangle is 8 cm more than the length of a side of the aware. find the length of a side of the equilateral triangle