When expanding number, we should separate the numbers according to the places like the number 275 written in expanded form 200+70+5. So, in this question we must likely done like this. The number is 39,005 the sum that is written on expanded form is 30,000+9,000+5.
I will get you started.
Let sin x = u
Then 7sin^2x -14sinx+2=-5 become
7u^2 - 14u = - 5
7u^2 - 14u + 5 = 0
Steps:
1. Solve for u.
2. Back- substitute for u.
3. Take the arcsin on both sides to find the angle(s).
You finish.
Answer
75r^4 t^2 + 25r^4 t^6
The hypothesis is sometimes the if part in my opinion