<span>A has earned twice as much as B so: A=2B
B has averaged 50% more than C so: B=C+0.5C
Combined is 220K, So A+B+C=220,000
The last equation can be re-written as:
2B+1.5C+C=220K
AND since A=2B, it can be rewritten again as:
3C+1.5C+C=220K
Now you can get C
finally, since B=1.5C you can get B, then to get the average, just divide that by 3 (years) and you should be done.
So B = 60000 for 3 years</span>
2x + 100 = 5x + 55
3x = 45
x = 15
2(15) + 100 = 130
180-130 = 50
so angle 2 is 50 degrees
Each girl will get 4 tangerines
1- peter
2-lia
3-kenny
4-jennie
5-harvey
6-joyce
7-rick
8-mark
Here is one way to show that the left side is identical to the right side.

Throughout the entire process, the right hand side stayed the same. When working on identities, it's important to keep one side the same while you transform the other side.
Despite the two sides being identical when simplified, there is the issue of cos(x) being zero in the denominator on the left hand side. Be sure to account for this when forming the domain. No such issue occurs on the right hand side. For instance, the value x = pi/2 leads to a division by zero error when in radian mode. So if I was your teacher, I would revise the "for any value of x" and replace it with something along the lines of "for any x value in the domain".