Answer:
I hope I know but I need help my self
There's no such thing as parallel or perpendicular "to a point". A problem like that
will always want the new line to be parallel or perpendicular to another <em><u>line</u></em>.
-- If the new line is parallel to the given line, then they have the <em><u>same</u></em> slope.
-- If the new line is perpendicular to the the given line, then the slope of the
new line is [ <em><u>1 / slope of the given line</u></em> ].
In either case, you now have the slope of the new line and a point on it.
From there, you should have no trouble finding its equation.
When any angle bisects with other angle then both the angles are equal.
Then, m of angle ABD = angle CBD
ABD = 70
ABD = CBD = 70°
ABC = 70 + 70 = 140°
