The distance between the point 4 3 and the inte... - JAMB Mathematics 2012 Question

P₁ (4, 3), P₂ (x, y)

y = 2x + 4 .....(1)

y = 7 - x .....(2)

Substitute (2) in (1)

7 - x = 2x + 4

7 - 4 = 2x + x

3 = 3x

x = 1

Substitute in eqn (2)

y = 7 - x

y = 7 - 1

y = 6

P₂ (1, 6)

Distance between 2 points is given as

D = (\sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2})

D = (\sqrt{(1 - 4)^2 + (6 - 3)^2})

D = (\sqrt{(-3)^2 + (3)^2})

D = (\sqrt{9 + 9})

D = (\sqrt{18})

D = (\sqrt{9 \times 2})

D = (3\sqrt{2})