Write an equation of the line containing the given point and parallel to the given line.

​(4​, -5​); 8x - 9y = 7

1 answer

To find the equation of a line parallel to a given line, we can use the fact that parallel lines have the same slope.

First, let's determine the slope of the given line. We can rewrite the equation 8x - 9y = 7 in slope-intercept form (y = mx + b), where m is the slope.

8x - 9y = 7
-9y = -8x + 7
y = (8/9)x - 7/9

The slope of the given line is 8/9.

Since the line we want to find is parallel to the given line, it will also have a slope of 8/9.

Now we can use the point-slope form of a line (y - y₁ = m(x - x₁)) to find the equation of the line passing through the point (4, -5) with slope 8/9.

y - (-5) = (8/9)(x - 4)
y + 5 = (8/9)x - 32/9

To simplify, let's multiply both sides of the equation by 9 to eliminate the fraction:

9(y + 5) = 8x - 32
9y + 45 = 8x - 32

Now we can rewrite the equation in slope-intercept form:

9y = 8x - 32 - 45
9y = 8x - 77
y = (8/9)x - 77/9

Therefore, the equation of the line containing the given point (4, -5) and parallel to the given line 8x - 9y = 7 is y = (8/9)x - 77/9.