Find the equation of a line which is from the... | JAMB UTME - Mathematics - 2015

Question 1 Report

Find the equation of a line which is from the origin and passes through the point (−3, −4)

y =

\frac{3 x}{4}

y =

\frac{4 x}{3}

y =

\frac{2 x}{3}

y =

\frac{x}{2}

Answer Details

Equation of a straight line is given by

y - y_{1} = m (x - x_{1})

Where m is the slope or gradient
Don't forget, the line passes through the origin. That means it has a coordinates of

{0, 0}

and

{- 3, - 4}

. So to calculate m

m = \frac{Δ y}{Δ x} = \frac{0 - (- 4)}{0 - (- 3)} = \frac{4}{3}

Equation of straight line is therefore given as:

y - (- 4) = \frac{4}{3} [x - (- 3)]

3 (y + 4) = 4 (x + 3)

3 y + 12 = 4 x + 12

3 y = 4 x

∴ y = \frac{4 x}{3}

Find the equation of a line which is from the origin and passes through the point (−3, −4)