Which relationship in the triangle must be true?
TE
sin(B) = sin(A)
sin(B) = cos(90 - B)
COS(B) = sin(180 - B)
COS(B) = cos(A)

Cosine stands for "complementary sine."  The sine of an angle is the cosine of the complementary angle and vice versa.  Complementary angles add to 90°.

sin(B) = cos(90 - B)

It's true for any angle, and it doesn't have much particularly to do with a triangle.

5050 i think

step-by-step explanation:

22, 28, 34, 40, 46

b)   f(n) = 6n + 16

n = what is the number of the row ( 22 would be row 1) so if we replaced n with 1, we would get 22

c)   the 14th row will have 100 seats

(1)   (2)   (3)   (4)   (5)   (6)   (7)   (8)   (9)   (10) (11) (12) (13) (14)

22 | 28 | 34 | 40 | 46 | 52 | 58 | 64 | 70 | 76 | 82 | 88 | 94 | 100