The graph of the equation x - 7y = -72, intersects the y-axis at P(α, β) and the graph of 6x + y - 15 = 0, intersects the x-axis at Q(γ, δ). What is the value of α + β + γ + δ?

Solution (By Examveda Team)

At y-axis, x = 0
0 - 7y = -42
y = 6
(α, β) = (0, 6)
At x-axis, y = 0
6x + 0 = 15
x = $$\frac{5}{2}$$
(γ, δ) = $$\left( {\frac{5}{2},\,0} \right)$$
α + β + γ + δ = 0 + 6 + $$\frac{5}{2}$$ + 0 = $$\frac{{17}}{2}$$