Mark is 15 years younger than Ashley. The sum of their ages is 55. What is a system if equations to find their ages?

True or False; In spherical geometry, a triangle can have, at most, two 90 degree angles.

Evaluate the expression 2x - 5 when x = 3? A) - 4 B) 1 C) 6 D) 11

Solve the following quadratic equation: - x2 = 4x

A piece of ribbon is cut into two shorter pieces in the ratio 2.8 : 1.25. The difference in the length of the two shorter pieces is 80.6 centimeters. What is the length of the original piece of ribbon?

A plane flying a straight course observes a mountain at a bearing of 30.3degrees to the right of its course. At that time the plane is 9 kilometers from the mountain. A short time later, the bearing to the mountain becomes 40.3degrees.

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.