Step-by-step explanation:
Let the two-digit number is 
<u>This can be written as:</u>
- 10x + y, where 1 ≤ x ≤ 9 and 0 ≤ y ≤ 9
<u>The difference between the number and product of its digits is:</u>
<u>Rewrite this as below:</u>
d = 10x - xy + y - 10 + 10 =
x(10 - y) - (10 - y) + 10 =
(x - 1)(10 - y) + 10
<u>We see that:</u>
- 0 ≤ x - 1 ≤ 8 according to the condition given above
- 1 ≤ 10 - y ≤ 10 again according to the condition given above
<u>The value of d is then:</u>
- 0 + 10 ≤ d ≤ 8*10 + 10
- 10 ≤ d ≤ 90
<h3>Proved</h3>
For this case, what you must do is to see in which scenario the speed of keeping constant during a certain time.
"A person biking on a trail at 1212 miles per hour for 2020 minutes"
We observe that the distance in this case is proportional to the time and the constant of proportionality is the speed.
In other words:
d = v * t
Answer:
the distance traveled is proportional to time in:
"A person biking on a trail at 1212 miles per hour for 2020 minutes"
Does this show answer like multiple choice
Breads/cereals;
11 * 140 = 1540 calories
Fruits/vegetables;
9 * 60 = 540 calories
Meat/milk;
x * 180 = 2800 - (1540 + 540)
180x = 2800 - 2080
180x = 720
x = 4 servings
