The equation of the line L1 is y=4x–8. The equation of the line L2 is 3y–12x+4=0. Show that L1 and L2 are parallel.

Parallel lines have the same gradient. The gradient of L1 is 4. For the gradient of L2: 3y=12x-4y=4x-4/3The gradient of L2 is also 4. Thus these lines are parallel.
Explanation 1.Rearrange the equation to make y the subject: 3y=12x-42.Divide through by 3 to get a single y as the subject: y=4x-4/3

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