#include "stdio.h"
#define false 0
#define true 1
int main() {
	int x, y, m, n, L, count=0, sA, sB, speDif, i;
	int state = false;
	scanf("%d %d %d %d %d", &x, &y, &m, &n, &L);
	if(m>n) {
		speDif = m-n;
		if(x>y) {
			for(i=0; i<speDif; i++) {
				if(((i+1)*L-x+y)%speDif == 0) {
					state = true;
					printf("%d", ((i+1)*L-x+y)/speDif);
					return 0;
				}
			}
			if(state == false) printf("Impossible");
		}
		else if(x<y) {
			for(i=0; i<speDif; i++) {
				if((i*L+y-x)%speDif == 0) {
					state = true;
					printf("%d", (i*L+y-x)/speDif);
					return 0;
				}
			}
			if(state == false) printf("Impossible");
		}
		else {}
	}
	else if(m==n) {
		printf("Impossible");
	}
	else {
		speDif = n-m;
		if(x>y) {
			for(i=0; i<speDif; i++) {
				if((i*L+x-y)%speDif == 0) {
					state = true;
					printf("%d", (i*L+x-y)/speDif);
					return 0;
				}
			}
			if(state == false) printf("Impossible");
		}
		else if(x<y) {
			for(i=0; i<speDif; i++) {
				if(((i+1)*L-x+y)%speDif == 0) {
					state = true;
					printf("%d", ((i+1)*L-x+y)/speDif);
					return 0;
				}
			}
			if(state == false) printf("Impossible");
		}
		else {}
	}
}