Question

Which function has the same graph as x + y= 11?

Answer 1

f(x) = 11 - x

Explanation:

We have to find a function that has a graph as x + y = 11.

Now, the equation given is

x + y = 11

⇒ y = 11 - x

So, if we consider x as an independent variable and y as a dependent variable whose values are dependent on the values of x, then er can write y = f(x) = 11 - x

So, the function f(x) = 11 - x has the same graph as x + y = 11. (Answer)

Answer 2

B. f(x) = -x + 11

Explanation:

The choices for this question are

A. f(x) = -y + 11

B. f(x) = -x + 11

C. f(x) = x − 11

D. f(x) = y − 11

First of all, we need to know that f(x) expresses the same variable than y, basically y=f(x).

Being said that, B and C are the viable choices, because the other ones don't make sense because they don't include the independent variable x.

One way to find the right answer is by taking the given expression and solving for y:

`x+y=11\\y=11-x\\f(x)=11-x=-x+11`

Therefore, the right choice is B. They have the same graph, because they have the same linear function.