How do you do proofs, how to understand it better

There are 4 keys on a keychain. One of the keys starts a car. If a key is randomly chosen, what is the probability that it starts the car A) 15% B) 25% C) 20% D) 5%

Where is the x-axis (where y is zero) in the inequality 5x+3y>450

What solution is this 2x=3x

What is the probability of getting a number less than 7 on a standard six-sided die

On a coordinate plane, a circle has a center at (8, 9). Concentric circles are circles with the same center but different radii. Which equations represent concentric circles along with the circle shown in the graph? Check all that apply.

If b does not equal 0 , can the solution set of ax = b be a plane through the origin?

Ramon earns $1,840 each month and pays $53.40 on electricity. To the nearest tenth of a percent, what percent of Ramon's earnings are spent on electricity each month?

The city of Hamden received money for improvements of the town's park. The park committee polled a random sample of 75 residents from the town. Of the 75 residents, 27 would like to see more trees planted in the park.

Intersecting lines forming linear pair which pair of angles is a linear pair?

A small publishing company is planning to publish a new book. The production cost to include a one-time fixed cost and variable cost. There are two production methods it could use.