Answer:
(a) The data set is a function, since for each input value {3,4,6,11} there is a single output value {5,7,11,21}
(B) A function is a mathematical relationship that associates one or more inputs with a single output value. So that the data set is not a function, there should be - for one or more values of the input - more than one output.
for example, if for the input value {3} there were two outputs {5, -5} then, the data set would not be a function.
The frelation
is not a function because:
When x = 1, y = +1 and y = -1.
(c) The set of data provided can be represented by the equation of a line of the form y = mx + b
The slope is:
![m=\frac{y_2-y_1}{x_2-x_1}](https://tex.z-dn.net/?f=m%3D%5Cfrac%7By_2-y_1%7D%7Bx_2-x_1%7D)
![m =\frac{7-5}{4-3}](https://tex.z-dn.net/?f=m%20%3D%5Cfrac%7B7-5%7D%7B4-3%7D)
m = 2
![b = y_1-mx_1](https://tex.z-dn.net/?f=b%20%3D%20y_1-mx_1)
b = 5 - 2*3
b = -1
Then, the function is:
y = 2x-1
You can substitute any of the points shown in the equation and check that equality is satisfied, for example:
(11 , 21)
y = 2 (11) -1
y = 22-1
y = 21. The equation is satisfied. The same goes for the rest of the values.