1. Let's call the number of carter school: "x" and "y" the number of alternative school. Then, you have that:
- T<span>he number of charter schools is 4 less than twice the number of alternative schools.
</span> - T<span>here are 48 charter schools in the country.
2. So, you have:
x=2y-4 (i)
x=48 (ii)
3. Then, when you substitute x=48 into the equation (i), you obtain:
</span>
x=2y-4
<span> 48=2y-4
4. Now, you must clear "y, as below:
48+4=2y
2y=52
y=52/2
y=26
</span><span>
How many alternative schools are in the county?
</span><span>
The answer is: There are 26 alternative schools.</span>
The double angle formula for the sine is

The right hand side is exactly your expression, where 
So, rewriting the expression from right to left, we have

Wow this question is very difficult,hold up
Answer:
m a g i c t h a t ' s h o w