5
First order equations include linear equations. In the coordinate system, the linear equations are defined for lines. A linear equation in one variable is one in which there is a homogeneous variable of degree 1 (i.e., only one variable). Multiple variables may be present in a linear equation. Linear equations in two variables, for example, are used when a linear equation contains two variables. Examples of linear equations include 2x - 3 = 0, 2y = 8, m + 1 = 0, x/2 = 3, and 3x - y + z = 3.
Total books borrowed = 8+4 = 12
No. of non - fiction books = 7
No. of fiction books = 12 -7
= 5
To learn more about linear equation , refer to brainly.com/question/26310043
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