View Compilation Error

991116_0_0_22525.c: In function `main':
991116_0_0_22525.c:9: error: `x' undeclared (first use in this function)
991116_0_0_22525.c:9: error: (Each undeclared identifier is reported only once
991116_0_0_22525.c:9: error: for each function it appears in.)
991116_0_0_22525.c:9: error: `y' undeclared (first use in this function)