If 3x + 2y = 7 and 4x - y = 24, then x - y = .
Equation (i) : 3x + 2y = 7
Equation (ii) : 4x - y = 24
Multiplying by 2 on both sides, => $$8x - 2y = 48$$ -----------(iii)
Adding equation(i) and (iii),
=> $$(3x + 8x) + (2y - 2y) = (7 + 48)$$
=> $$11x = 55$$
=> $$x = \frac{55}{11} = 5$$
Substituting it in equation (ii), we get : $$4(5) - y = 24$$
=> $$y = 20 - 24 = -4$$
$$\therefore (x - y) = 5 - (-4) = 5 + 4 = 9$$
=> Ans - (A)
Create a FREE account and get:
