1. Control Structures A Lecture By Abdul Ghaffar Khan

13. The if-else statement: (Example 7.3 Quadratic Equation )

14. The if-else statement: (Example 7.3 Quadratic Equation ) #include <stdio.h> #include <conio.h> #include <math.h> void main(void) { int a, b, c; double d, x1, x2; //clrscr(); printf(&quot;Input a=&quot;); scanf(&quot;%d&quot;,&a); printf(&quot;input b = &quot;); scanf(&quot;%d&quot;,&b ); printf(&quot;input c = &quot;); scanf(&quot;%d&quot;,&c ); d = b*b -4*a*c; if (d<0) { printf(&quot;Roots are not real&quot;); printf(&quot;Enter some other values of a, band c&quot;); } else { x1 = ( -b - sqrt( d )) / (2 * a); x2 = ( -b + sqrt( d )) / (2 * a); printf(&quot;First Root is %.2f&quot;,x1); printf(&quot;Second Root is %.2f&quot;,x2); } getch(); }

18. Example 7.4