A = 4a-9b Solve for a

Which ratio is equivalent to 15 : 42 a) 5 : 12 b) 10 : 28 c) 36 : 48 d) 5 : 21

Two numbers a and b as such that the sum of 5% of a and 4% of b is 2/3 of the sum of 6% of a and 8% of b. find the ratio of a:b

Make h the subject of the formula A=2 (pi) r (r+h)

Find the slope of the line: (8,-2) and (-7,4).

What's the greatest common factor

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.