Simplify the expression by using a double-angle formula. - 2cos2π91

Which trigonometric function has the same value as sin 75? cos 75 cos 15 sin 15 tan 75

Kristel is considering hiring a moving company. Sanford's Plus charges an initial fee of $125 plus $165 per hour. Quality Moving Company charges an initial fee of $200 plus $145 per hour.

Write your own problem. Choose a secret number. Write clues about the number using the words is greater than and is less than.

Is this expression contain a variable? 7+15n

Cameron is designing a calendar as a fundraising project for math class. The cost of printing is $500, plus $2.50 per calendar. Cameron estimates the math class will sell 200 calendars.

Are all cubes congruent

Find the normal form of the equation of the plane that passes through p = (0, - 4, 5) and is parallel to the plane with general equation 3x - y + 5z = 3.

Five times a number x minus 9 is two thirds of a number y. What is the equation?

The maximum weight an airline allows for a suitcase is 50 pounds. Ella's suitcase weighs 8 pounds empty. If Ella meets the requirements, what could be the weight of the contents of her suitcase?

A flight instructor charges $50 per lesson, plus an additional fee for the use of his plane. The charge for the use of the plane varies directly with the square root of the time the plane is used.