A+B=25.6
A+C=41.6
B+D=25.6
C-D=19.2

Solve for A, B, C, and D.

Step-by-step explanation:

Let's get some organization going here and number the equations:

1. A+B=25.6

2. A+C=41.6

3. B+D=25.6 and

4. C-D=19.2

First I am going to solve equation 1 to get new equation 5:

5. B=25.6-A (hold that for a sec) and then solve equation 2 to get new equation 6:

6. C=41.6-A

Now sub equation 5 into equation 3:

25.6-A+D=25.6 and

A-D=0 so

A=D. That's good. Now we move on:

Sub equation 6 into equation 4 to get

41.6-A-D=19.2. But since A = D:

41.6-D-D=19.2 so

41.6-2D=19.2 and

-2D=-22.4 so

D = 11.2 and so does A.

Now we will fill in to get B and C.

In equation 2, with A = 11.2:

11.2+C=41.6 so

C = 30.4.

For B, use the fact that D = 11.2 in equation 3:

B+11.2=25.6 so

B = 14.4

All in all:

A = 11.2

B = 14.4

C = 30.4

D = 11.2

Yikes!!

hope it you

step-by-step explanation:

sin(7pi/6 - pi/3)  

= sin(7pi/6 - 2pi/6)  

= sin(5pi/6)  

= sin(pi - pi/6)  

= sin(pi/6)  

= 1/2  

sin 7pi/6 - sin pi/3  

= sin (pi + pi/6) - sin pi/3  

= -sin pi/6 - sin pi/3  

= -1/2 - sqrt(3)/2  

= -(1+sqrt(3))2