Find an explicit rule for the nth term of the sequence. The second and fifth terms of a geometric sequence are 20 and 1280, respectively.

If the value of cos330°is√3/2 then find cos 165°.

Which of the following represents the factorization of the trinomial below? x^2+7x-30

The students at jefferson middle school are raising money for a charity by selling t-shirts and hats. the number of t-shirts sold was 3 times the number of hats. the profit was $5 for each t-shirt sold and $2.50 for each hat sold. the students raised $840 for the charity. they used the system below to analyze their success and found the solution to be (144, 48). 5x+2.50y=840 x=3y how much did they earn from t-shirt sales?