is in quadrant I, so
.
is in quadrant II, so
.
Recall that for any angle
,

Then with the conditions determined above, we get

and

Now recall the compound angle formulas:




as well as the definition of tangent:

Then
1. 
2. 
3. 
4. 
5. 
6. 
7. A bit more work required here. Recall the half-angle identities:



Because
is in quadrant II, we know that
is in quadrant I. Specifically, we know
, so
. In this quadrant, we have
, so

8. 
Answer:
21 students
Step-by-step explanation:
25% of 28 is 7 28-7=21
Answer:
y=7+3x
Step-by-step explanation:
Since she already has 7 in her account and she ADDS 3 more each day you would multiply 3 by x which represents the number of days and add that to seven because she already had it. This would equal to Y which represents the total in her account
A)
Triangle ABX
Height = 8m
Base = 26-11 m
Find length by AB^2 = 15^2 + 8^2
b) Find AC by using AB as Height and BC as base
AC^2 = AB ^2 + BC ^2