Multiply the following two linear functions:
(x+3)(2x+5)
Answer :
Explanation:
The standard format of a Linear Function is as follows:
f(x) = ax + b
It is important to keep in mind the following regarding Linear Functions:
1. The term “Linear” is derived from the word “Line”. Therefore a Linear Function is a function or equation of a straight line.
2. The degree of this function is always 1 (a degree means the highest power or exponent
The variable in the function is raised to.
Therefore by looking at the two sets of functions presented in this problem we can identify
(x+3) as one linear function and also (2x+5) as another linear function and the requirement of
this problem is to multiply the two and end up with a resulting quadratic equation.
In order to perform the multiplication we use a method called FOIL which stands for:
First – Outer – Inner – Last
Lets now identify those terms in the above linear functions:
First terms : (x) in the first function (x+3) and the (2x) in the (2x+5) function
Outer terms : (x) in the first function (x+3) and the (5) in the (2x+5) function
Inner terms : (3) in the first function (x+3) and the (2x) in the (2x+5) function
Last terms : (3) in the first function (x+3) and the (5) in the (2x+5) function
Now let us implement the above multiplication:
Notice that the middle like terms of 5x and 6x are combined and thus results in 11x as the middle term for the resulting quadratic function.
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