Assignment 1

This assignment deals with the concept of simple assignments and with simple branching instructions.

A circle (in the two-dimensional real plane) is defined in terms of three real numbers a,b,c. The defining equation is taken to be:

   x2 + y2 + ax + by + c = 0.

Input three real numbers a,b,c from the user. Then determine if these three numbers define a circle. If not, print a diagnostic message and quit. Otherwise determine (and print) the center and radius of the circle. Also input the coordinates of a point. Print whether this new point lies on, inside or outside the circle.

Sample run

   Enter the coefficients of the defining equation :
   a = 1
   b = 1
   c = 1
   These a,b,c do not define a circle.

   Enter the coefficients of the defining equation :
   a = 3
   b = -2
   c = -0.75
   The circle has center at (-1.500000,1.000000) and radius 2.000000.
   Enter the coordinates of a point :
   x = 0
   y = 0
   The point is inside the circle.

Test output

Report the output of your program on the following input values. Ignore the x,y values, if they are not needed.

• a = 1, b = 1, c = -1, x = -1, y = 1.

• a = 6, b = 8, c = 9, x = -3, y = 0.

• a = -1.1, b = -2.2, c = 9.9, x = 1.1, y = -3.3.

• a = -3.14, b = 2.78, c = -9.87, x = 2, y = 2.

Note

You may use the sqrt function of the math library (#include <math.h>). Also compile your program with the flag -lm.

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