Respuesta :
The expression for y is y = 2x +20; x is any integer greater than or equal to 0, and y is an integer greater than or equal to 20
How to form mathematical expression from the given description?
You can represent the unknown amounts by the use of variables. Follow whatever the description is and convert it one by one mathematically. For example if it is asked to increase some item by 4 , then you can add 4 in that item to increase it by 4. If something is for example, doubled, then you can multiply that thing by 2 and so on methods can be used to convert description to mathematical expressions.
What is domain and range of a function?
Domain is the set of values for which the given function is defined.
Range is the set of all values which the given function can output.
We're given that:
- Time spent by Vlad on history homework = 20 minutes
- Time spent by Vlad on math homework (x math problems) = 2 minutes on each problem
- y = time he spent on doing overall homework
Then we have:
y = time on math homework + history homework
y = 2 +2 +2 ... (x times) + 20 minutes
[tex]y = 2x + 20[/tex]
x is "number of math problems". Thus, x can be 0,1,2,... These numbers are called non-negative integers(or integers greater or equal to 0) or whole numbers.
y is the time taken, but we see that
y = 2 times (non-negative integer) + 20
y = positive integer times non-negative integer + positive integer
Thus, we have:
y = non-negative integer + positive integer = positive integer
Thus, y assumes positive integral values only (in minutes).
Also, y is always going to be at least 20 (as history homework is going to take 20 minutes, even if math homework is nill ).
Thus, the expression for y is y = 2x +20; x is any integer greater than or equal to 0, and y is an integer greater than or equal to 20
Learn more about domain here:
https://brainly.com/question/20073127
