Please simplify sin(6x)•cos(2x) - cos(6x)• sin(2x) A. Cos 4x
B. Cos 8x
C. Sin 8x
D. Sin 4x

but there’s no any figure there!

ιт ωαѕ 5¢м вє¢αυѕє 1/4 σf 20 ιѕ 5

αи∂ 5*4=20

нσρє ι ¢συℓ∂ нєℓρ уσυ

look at the picture.

1.

ef : ab = 2 : 3

gf : cb = 2 : 3

gh : cd = 2 : 3

he : da = 2 : 3

2.

∠a ≅ ∠e

∠b ≅ ∠f

∠c ≅ ∠g

∠d ≅ ∠h

3.

use pythagorean theorem:

the length of the abcd trapezoid sides:

|ab| = 3 cm

|bc| = 10 cm

|cd| = 3(3) cm = 9 cm

|da| = 8 cm

the perimeter of abcd = 3 + 10 + 9 + 8 = 30 cm

the ratio of perimeters of the tarapezoids is equal 2 : 3.

substitute:

      cross multiply

      divide both sides by 3