If x y 2y - x 1 5 find the value of x - WAEC Mathematics 2012 Question

x + y = 2y - x + 1 = 5

x + y = 2y - x + 1

x + x + y - 2y = 1

2x - y = 1....(i)

2y - x + 1 = 5

-x + 2y = 5 + 1

-x = 2y = 4

x - 2y = -4 .....(ii)

solve simultaneously (i) x 2x - y = 1

(ii) x x - 2y = -4

2x - y = 1

=2x - 4y = -8

3y = 9

y = \(\frac{9}{3}\)

y = 3

substitute y = 3 into equation (i)

2x - y = 1

2x - 3 = 1

2x = 1 + 3

2x = 4

x = \(\frac{4}{2}\)

= 2