getting the value, which a pointer is pointing to - c

Question

I am having some trouble with an assignment. I am trying to read the lines from a txt file (line by line) split the values and calculate the quadratic formula from them; the lines always contain a, b and c. However, I came to a problem where it looks like when I come to the formula the values seem to be the pointer position instead of the value assigned. I don't think the finalArrayOfValues should be a char* but the code wouldn't compile without it. Is there any way to retrieve the value from the pointer or should I try a different solution?
Apologies in advance if this is trivial (coming from javascript and python) I am quite new to c,
Thank you.
#include <math.h>
#include <stdio.h>
#include <string.h>
int main(void) {
double a;
double b;
double c;
double d;
char arrayOfValues[100][128];
char lines[128];
char *finalArrayOfValues[3];
int i = 0;
double root1, root2;
FILE *file; /* declare a FILE pointer */
file = fopen("QFData1.txt", "r");
int count = 0;
while (fgets(lines, 128, file)) {
strcpy(arrayOfValues[count], lines);
printf("line %d: %s\n", count, arrayOfValues[count]);
count++;
}
char *string = arrayOfValues[1];
char *token = strtok(string, ",");
// loops through the string to extract all other tokens
for (int n = 0; n < 3; n++) {
finalArrayOfValues[i] = token;
printf(" %s\n", token);
token = strtok(NULL, ",");
i++;
}
printf(" %s\n", finalArrayOfValues[0]);
printf(" %s\n", finalArrayOfValues[1]);
printf(" %s\n", finalArrayOfValues[2]);
a = finalArrayOfValues[0] - "0";
b = finalArrayOfValues[1] - "0";
c = finalArrayOfValues[2] - "0";
printf(" %f\n", a);
printf(" %f\n", b);
printf(" %f\n", c);
d = b * b - (4 * a * c);
printf(" %f\n", d);
// real roots
root1 = (-b + sqrt(d)) / (2 * a);
root2 = (-b - sqrt(d)) / (2 * a);
printf("First root = %.2lf\n", root1);
printf("Second root = %.2lf\n", root2);
return 0;
}