Question

The value of p if (21,1) is a solution of px + 12y = 7 is

Answer 1

p*21 + 12*1 = 7
p*21 = 7-12
p*21 = -5
p= -5/21

Answer 2

Px + 12y = 7
given x = 21 and y= 1

p(21) + 12(1) = 7
21p + 12 = 7
21p = 7 - 12
21p = -5
p = -5/21