Trigonometry
Angle Sum and Difference, Double Angle and Half Angle Formulas
Find the exact value of:
Sin 85* cos 20* - Cos 85* sin 20*

sin(105)

Step-by-step explanation:

Apply the trig identity: sinAcosB+cosAsinB = sin(A+B)

integrating that into the question to find A and B

sin(85)cos(20)+cos(85)sin(20)

= sin(85+20) = sin(105)

1. 22

2. 1

3. 7

4. 18

step-by-step explanation

e2020 got it right

x > 1.3

step by step:

8.5−0.9x> 9.8−1.9x

step 1: simplify both sides of the inequality.

−0.9x+8.5> −1.9x+9.8

step 2: add 1.9x to both sides.

−0.9x+8.5+1.9x> −1.9x+9.8+1.9x

1x+8.5> 9.8

step 3: subtract 8.5 from both sides.

1x+8.5−8.5> 9.8−8.5

1x> 1.3

step 4: divide both sides by 1.

1x/1 > 1.3/1