Question 66155
C street has an x-intercept of -8 and a slope of 2. use the x-intercept point to write the equation of c street in point slope form.
Answer: y-0=2(x+8)<--you had a type-o.
You get this because the x-intercept is (-8,0) and the slope, m=2
The point-slope formula is {{{highlight(y-y1=m(x-x1))}}}, where m=slope and (x1,y1) is a given point on the line.
Good job: {{{y-0=2(x+8)}}} is right.
:
 
D street crosses c street  at the point (-10,-4) and is perpendicular to the y-axis.  Determine the y-intercept point and write the equation of d street. 
A line that is perpendicular to the y-axis is horizontal.  Horizontal lines have a slope of m=0
{{{y+4=0(x+10)}}}
{{{y+4=0}}}
{{{y=-4}}} <---the equation of a horizontal line always ends up being y=k, where k is a constant and there is no x.  Notice that k is the y component of the point it went through.  That also always happens.
The y-intercept is (0,-4), because all the points on a horizontal line have the same y-value.
:
G street crosses f street at the point (3,7) and is parallel to d street. Determine the y-intercept point of g street and write the equation of g street.
If G is parallel to D, then it is also horizontal, so the equation of a horizontal line going through (3,7) is:
{{{y=7}}}
Its y-intercept is: (0,7)
Happy Calculating!!!