Question

Write the slope intercept equation of a line which is parallel to y=3x+5 passing through (-6,3). Can anyone please explain with the formula?

Answer 1

y = 3x + 21

Explanation:

The formula of a line goes in y= mx + c

Parallel lines have different y-intercepts but the same gradients so we can assume that

y = 3x + c

Substitute in the coordinates (-6 , 3) to work out the full equation

3 = -18 + c

So c = 21

Therefore the equation of the line that is parallel to y=3x+5 passing through (-6,3) is y = 3x + 21

Answer 2

Remember that the slope intercept formula is:

y = mx + b

m is the slope

b is the y-intercept

If lines are parallel then they have the same slope (m)

This means that the slope of the line will be 3 :

y = 3x + b

Now we must find b

To do that you must plug in the point the line goes through in the x and y of the equation.

(-6, 3)

3 = 3(-6) + b

3 = -18 + b

21 = b

y = 3x + 21

Hope this helped!

~Just a girl in love with Shawn Mendes