1)

Question

6m+n=47
m-4n=12

can someone help me solve using substitution method?

Answer 1

6m+n=47 --- (1)
m-4n=12 --- (2)

From (2),
m = 12 + 4n --- (3)

sub (3) into (1),
6(12 + 4n) + n = 47
72 + 24n + n = 47
25n = -25
n = -1

sub n = -1 into (3),
m = 12 + 4(-1)
m = 8

CHECK: sub m = 8 and n = -1 into (2),
8 - 4(-1) = 12