Question 2455
4x -y = -1
=> 4x + 1 = y
=> y = 4x + 1........Equation (1)

6x + 5y = 18...equation(2)
Substituting the value of y from equation(1) in the equation(2)

=> 6x + 5(4x+1) = 18
=> 6x + 20x + 5 = 18
=> 26x = 18 -5
=> 26x = 13
=> x = 13/26 = 1/2

substituting the value of x in equation(1)
y = 4x + 1
y = 4*1/2 + 1
y = 2+1 = 3

So, x=1/2 y=3

Hope this helps :-)