|
Question 377880: Hello! I am trying to find the slope-intercept form of the equation of the line through the point (-1, 2) parallel to the lind -4x-9y=-7. Thank so much! I seem to be completely confused on this concept.
Denise Bissell
Answer by nyc_function(2741)   (Show Source):
You can put this solution on YOUR website! The first thing to do is isolate y in the given equation.
-4x - 9y = -7
-9y = 4x - 7
y = (-4/9)x + 7/9
The equation we are searching for must have the same slope as the equation
y = (-4/9)x + 7/9 because equations that are parallel to each other have the same slope. The slope is the fraction next to x. In other words, the slope is (-4/9).
We now use the given point (-1,2) and the slope (-4/9) and plug that into the point-slope formula.
y - d = m(x - c)...This is the point-slope formula. In your math book, the formula probably looks like this: y - y1 = m(x - x1) but it does not matter which letters we use in the formula.
Given point is (-1,2) = (c,d).
The slope is m = (-4/9)
We now plug and chug.
y - 2 = (-4/9)(x - (-1))
y - 2 = (-4/9)(x + 1)
y - 2 = (-4/9)x -4/9
y = (-4/9)x - 4/9 + 2
y = (-4/9)x + 14/9
Done!
|
|
|
| |
