There isn't enough information; however, let's say you were to find the missing side length of a rectangle. The perimeter is 52 and the two given side lengths are both 16. You would set up an equation to find the missing side lengths:
52 = 16 + 16 + ? + ?
52 = 32 + ? + ?
20 = ? + ?
Since this is a rectangle, the two other sides have to be equal. Therefore, you would divide the number by 2.
10 = ?
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 = 2

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.
The absolute value is the value of the number without the sign. So in this case it's 3 and -3
X(x-1)(x^2+4)=(x^2-x)(x^2+4)=(x^4)+(4x^2)-(x^3)-(4x)=(x^4)-x(x^2+4)+(4x^2)