what is the gradient for a line parallel to y = 3x + 5 ???
3 : the gradient stays the same for parallel lines
y intercept (c) = value of y when x=0
the form of the equation of a straight line is y = mx + c where m is the gradient and c is the y intercept
if two points are given, we can find the gradient using the formula m = (change in y)/(change in x)
to find the equation of a straight line from two points, substitute one point into the general equation and solve for c then use the other point to check that it satisfies the equation
