SOLUTION: Please I need your help in solving this problem: The straight line L is parallel to y + 3x =1 and passes through the point P(2,3). Find its x-intercept. 1. x-intercept =

Algebra ->  Linear-equations -> SOLUTION: Please I need your help in solving this problem: The straight line L is parallel to y + 3x =1 and passes through the point P(2,3). Find its x-intercept. 1. x-intercept =       Log On


   

Question 300293: Please I need your help in solving this problem:
The straight line L is parallel to y + 3x =1
and passes through the point P(2,3). Find its x-intercept.
1. x-intercept = 9/4
2. x-intercept = 3
3. x-intercept = 10/3
4. x-intercept = -3
5. x-intercept = -1
Thank you so much.
Answer by Stitch(470) About Me  (Show Source):
You can put this solution on YOUR website!
The equation of a line is Y+=+mX+%2B+B
Where m = the slope & B = the Y-intercept.
The X-intercept is found when Y = 0.
Two lines are parallel when they have the same slope. So in order to find the slope of line L, we need to find the slope of the other line.
Rewrite Y + 3X = 1 into standard form to find the slope
Y+=+-3X+%2B+1
Y+=+highlight%28-3%29X+%2B+1 The slope is -3
Now we need to use the cordinates that were given to find the equation of the line. We were given (2,3) So when X = 2, Y will equal 3.
Put that into the standard form
3+=+-3%2A%282%29+%2B+B Simplify
3+=+-6+%2B+B Add 6 to both sides
highlight%289+=+B%29
Now we have the equation of line L
Y+=+-3X+%2B+9 Now we need to set Y = 0 to find the X-intercept
0+=+-3X+%2B+9 Subtract 9 from both sides
-9+=+-3X Divide both sides by -3
highlight%283+=+X%29 The X-Intercept is 3 at (3,0)