If a * b means 2a + b, then what is 2*5?

A: 7

B: 9

C: 12

D: 14

E: none of the above

How do I solve 3x-7y=63 and 4x+3y=-27by addition?

Two buses leave Houston at the same time and travel in opposite directions. One bus averages 55 mi/h and the other bus averages 45 mi/h. When will they be 400 mi apart?

Circle A has a radius of 21 meter circle b has a radius of 28 meters. Is the relationshio between the radius and circumference the same for all circles

A room has the following dimensions: L : 16' W: 12' H : 10' What is the area of the room?

Element X decays radioactively with a half life of 12 minutes. If there are 510 grams of Element X, how long, to the nearest tenth of a minute, would it take the element to decay to 11 grams?

Use full sentences to describe why the product of x^3 and x^7 is x^10

What is the domain? y = - 3x2+4x-6

60 customers per hour arrive randomly (i. e., cva = 1) and randomly join one of 6 unpooled queues. each of the six employees can handle exactly 15 customer requests per hour (i. e., no variability).

Maghan works at an ice cream truck and makes $8.25 per hour. lucas works for a ladscape and makes $6.50 per hour. how much more does meghan make each hour?

A triangle has height 15in. and area 120in squared. what is the length of its base?