(If a were zero, you would have a linear equation.) Through this equation ... and is perpendicular to the axis of symmetry. The focal distance of a parabola is the distance from the vertex ...

Watch this video to learn about the equation of a straight line. Since we are given 2 points that already lie on the line, using the formula as before, we need to calculate the gradient first.

The straight line through two points will have an equation in the form \(y = mx + c\). Then, we can find the value of \(c\), the \(y\)-intercept, by substituting the coordinates of one point into ...