Area of Trapezoid using function

#include<stdio.h>
double getArea(int a, int b, int h);
int main()
{
    int num1,num2,num3;
    printf("Enter the value of a,b and h: ");
    scanf("%d %d %d",&num1,&num2,&num3);
    printf(" Trapezoid Area:%.2lf", getArea(num1,num2,num3) );

    return 0;
}
double getArea(int a, int b, int h)
{
    double area;
    area= (0.5*(a+b)*(double)h);
    return area;
}