Equation of a straight line

Watch this video to learn about the equation of a straight line.

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The general of a straight line is \(y = mx + c\), where \(m\) is the gradient and \((0,c)\) the coordinates of the y-intercept.

Look at the National 4 straight line section before continuing.

We can find the equation of a straight line when given the gradient and a point on the line by using the :

\(y - b = m(x - a)\)

where \(m\) is the gradient and \((a,b)\) is on the line.

Find the equation of the line with gradient 3, passing through (4, 1).

Using \(y - b = m(x - a)\) with m = 3, a = 4 and b = 1.

\(y - 1 = 3(x - 4)\)

\(y - 1 = 3x - 12\)

\(y = 3x - 11\)

Now try the example question below.

Find the equation of the line which passes through the points A(-2, 0) and B(1, 6) and state the gradient and .