# Linear interpolation

To the mobile version
 Coordinates of points: x1 = y1 = x2 = y2 = Equation of line: m = b = Interpolation: x3 = y3 =

Rounding: significant digits.
Decimal sign:

With this calculator you can determine the parameters a and b of the equation of a line y = m·x + b from the coordinates of two points (x1|y1) and (x2|y2). Alternatively, you may use the coordinates of one point and one parameter (a or b) or the whole equation of line as input. After the equation of the line has been calculated or typed in completely, the coordinates of other points (x3|y3) may be calculated when one of the coordinates (x3 or y3) is given.

Usage: Type the known values (coordinates or parameters of the equation of a line) into the corresponding fields. A possible calculation is performed after the next click on any free space of the window or the "calculate" button. Fields of input values will be coloured light green while fields of output values are coloured pink.
When you change an input value, the equation of a line is calulated again by using the two values as input, which have been changed last.
After the equation of the line has been calculated or typed in completely, the fields for the additional coordinates x3 and y3 get a light coloured background. Now, you may type values into these fields. After the input of one value the other value will be calculated.
Input data not valid will be deleted before the calculation and will not be used.

Example: Two points have the coordinates (1|3) and (2|5). Type these values into the corresponding fields. After a mouse click on a free space of the window or the "calculate" button the equation of a line is calculated. You get the result y = 2·x + 1.
Now you may calculate other points on this line. E. g. type the value of "-3" for x3. After a mouse click on any free space of the window or the "calculate" button you get a value of "-5" as y-coordinate of this point.

Remarks: