Can someone solve this and tell me how they did it? the difference between a number and twenty is equal to the product of five and a number.

Astudent showed the steps below while solving the inequality |x-4|< 1 by graphing.

Amotorboat maintained a constant speed of 12 miles per hour relative to the water in going 45 miles upstream and then returning. the total time for the trip was 8.0 hours. use this information to find the speed of the current.

Heather, sarah, nicky, and jill each have nine markers. how many markers do they have in all?