Question

A function with an input of 1 has an output of 3. Which of the following could not be the function equation?options:y = 3 xy = - x + 4y = x - 2y = 2 x + 1

Answer 1

Solution:

A function with an input of 1 has an output of 3.

This means that

$when\text{ }x=1,y=3$

Step 1:

We will try the first option

$\begin{gathered} y=3x \\ y=3(1) \\ y=3 \\ (1,3) \end{gathered}$

Step 2:

We will try the second option

$\begin{gathered} y=-x+4 \\ y=-1+4 \\ y=3 \\ (1,3) \end{gathered}$

Step 3:

We will try the third option

$\begin{gathered} y=x-2 \\ y=1-2 \\ y=-1 \\ (1,-1) \end{gathered}$

Step 4:

We will try the fourth option

$\begin{gathered} y=2x+1 \\ y=2(1)+1 \\ y=2+1 \\ y=3 \\ (1,3) \end{gathered}$

Hence,

The final answer is

$\Rightarrow y=x-2$