How does one know the domain and range of the linear function y=-5+2x?

Question

I know the answer is domain- 0 is less than or equal to x, while 10 is greater than or equal to x. Range- -6 is less than or equal to y, while -1 is greater than or equal to y. I don't understand why this is though?

Answer 1

To find the Domain ask yourself:" what values can x have?"
The answer is x can be any real number, including irrational numbers and both positive and negative numbers. There is nothing to restrict the value that x can have.

To find the range ask yourself:"What values can y have?" and again the answer is all the real numbers because for each value of x there is a unique value for y.

Answer 2

domain is the input variables, (x) is the domain,
Range is the output variables, (y) is the range.

There are no numbers for the domain and range until you assign a set of values or domain for (x) then you can find the range (y). So you solution is: DOMAIN = X , RANGE = Y.

If you wanted to solve it with numbers it would go like this:
Single solution Example:
x=2 (domain) , y = -1 range. (y=-5+2*2)

Example for a set of values:
If the domain is 0 The range will be (y=-5+0) which = -5 as the low end,
(y=-5+20) which =15 as the high end.
therefore the range is -5

Answer 3

FINDING DOMAIN:
Since domain means ,the values of x,for which function y is defined.
now since ,in this case , y is defined for every real value of x ,so domain consist of every real number.
Domain= R
R denotes every real number

FINDING RANGE:
Range means all the values of y, which y takes for every value of x of its domain.
here y is taking all values on real number line for every value of x in its domain.

TIPS
1. The best way of finding domain and range ,is to plot its graph.
in this case,since it is linear function, the graph is straight line.

2 The range and domain of all linear functions is R.

Answer 4

the is pon. so
domain=R
range=R