Question

PLEASE HELP ASAP

The graph below shows four straight lines, A, B, C, and D:


Graph of line A going through ordered pairs negative 2, negative 3 and 2, 5. Graph of line B going through ordered pairs negative 2, negative 4 and 2, 4. Graph of line C going through ordered pairs negative 2, negative 5 and 3, 5. Graph of line D going through ordered pairs 0, negative 4 and 4, 4


Which line is represented by the function f(x) = 2x + 1?

Answer 1

line a

Explanation:

Answer 2

Line A is represented by the function f(x) = 2x + 1.

Explanation:

This can be solved by trial and error. What it means? It means that we are going to replace the ordered pairs in the function, and the equality must be satisfied.

Line A

(-2,-3)

When x = -2, f(x) = -3. Does it happen in the function?

`f(x) = 2x + 1`

`-3 = 2(-2) + 1`

`-3 = -3`

The first equality is OK. Let's see the second

(2,5)

When x = 2, y = 5.

`f(x) = 2x + 1`

`5 = 2(2) + 1`

`5 = 5`

Also OK.

So line A is represented by the function f(x) = 2x + 1.

Now let's see why the other lines are not represented by this function.

Line B

(-2,-4)

`f(x) = 2x + 1`

`-4 = 2(-2) + 1`

`-4 = -3`

False

Line C

(-2,-5)

`f(x) = 2x + 1`

`-5 = 2(-2) + 1`

`-5 = -3`

False

Line D

(0,-4)

`f(x) = 2x + 1`

`-4 = 2(0) + 1`

`-4 = 1`

False