What shapes are perpendicular sides only?

Which is the better buy $60 and 6 CDs or $72 and 8 CDs

In morning Emily studied 40 minutes for a math exam. Later that evening Emily studied for x more minutes. Write an equation that represents the total number of minutes y emily studied for the math exam.

7. Dan used 1 cups of sugar to make brownies. He now has 4 cups of sugar left. How much sugar did he have before he made brownies? Write and solve the equation

What are the binomial factors of the expression below? x^2 + 7x+12

36.) The equation of a circle with center (3,-4) and a radius of 4 is:

A newspaper reporter wants to know how popular the hobby of bird watching is in the city. He asked people at the local bird refuge if they watched birds as a hobby. Which of the following best explains whether the reporters data is valid or not?

I am very confused on how to figure out if y = 3/4x is proportional?

Alison wants to buy a mountain bike for $339.12. If she saves $28.26 each month, in how many months will she be able to buy the bike?

At 12 o'clock the temperature was 7°C. The temperature decreased by - 20°C. What is the new temperature?

Ashleys rentals charges $27.50 per hour to rent a surfboard and a wetsuit. Darlas surf shop charges $23.25 per hour to rent a surfboard plus $17 extra for a wetsuit.