In math, a function will relate every input value to the output values in a manner that there will be a relationship between the x values to the y values.
In this case;
x y
0 3
2 7
4 11
To know if this is a function, find the relationship between x values and y values.
First find the slope / gradient assuming the values will result to a linear relationship {the first test]
So, slope m = change in y values / change in x values
m= 7-3/2-0 = 4/2 = 2
The gradient is 2, now lets find the equation
2= y-3 / x-0
2{x-0} = y- 3
2x= y- 3
2x + 3 = y
y= 2x + 3 ------the equation for the relationship which means;
For every value of y, you take the value of x , multiply it by 2 then add 3.
For example;
If x is 6, y will be 2*6 + 3 = 12 + 3= 15
This shows that there is a relationship between the values of x and y represented by the function;
f{x} = 2x + 3
Answer
Yes.