Question

If  2x + cy = 8 and x =  y = 4, then c equal
(a)4
(b)8
(c) 0
(d) 1​

Answer 1

Answer:

2x - cy = 8 and x =y

so, 2x - cx = 8

x (2 - c) = 8

x = 8 / (2-c)

denominator should not be zero

so, 2 - c = 0

c = 2

except value of c=2 the solution can be founded.