Question

Find x by cross multiply 3x-y-3=0;4x-y-8=0

Answer 1

Solution :

3x - y - 3 = 0

3x - y = 3

x = 3 + y / 3 ----(1)

4x - y - 8 = 0

4x - y = 8

x = 8 + y/4 ---- (2)

Therefore,

3 + y / 3 = 8 + y /4 ---(From 1 & 2)

4(3 + y) = 3(8 + y)

12 + 4y = 24 + 3y

4y - 3y = 24 - 12

y = 12

Substituting the value of y in eq(1)

x = 3 + 12/3

x = 15/3

Therefore , x = 5

Hence Proved

Answer 2

Answer:

method cross multiplication

3x-y=3 ; 4x-y=8