Answer:
m = -1, c = 2
Step-by-step explanation:
if A ( 3, 5) and B (1, 4) lie on the graph of the line mx + cy = 7, then their coordinates satisfy the equation of the line:
A: [tex]3m+5c=7[/tex]
B: [tex]m+4c=7[/tex]
From the second equation:
[tex]m=7-4c[/tex]
Substitute it into the first equation:
[tex]3(7-4c)+5c=7\\ \\21-12c+5c=7\\ \\-12c+5c=7-21\\ \\-7c=-14\\ \\c=2\\ \\m=7-4\cdot 2=7-8=-1[/tex]
