99.1k views
5 votes
An equation of the line in the XY-plane containing points (0, -9) and (-3, 0) is given as Ax + By = 8. What is the value of 'B'?

a) 3
b) -3
c) 4
d) -4

1 Answer

3 votes

Final answer:

Using the given points, the slope of the line is calculated as -3. Substituting into the slope-intercept form, and rearranging to the standard form 'Ax + By = 8', we find 'B = 1', which is not among the options, indicating a possible error in the provided question.

Step-by-step explanation:

To find the value of 'B' in the equation 'Ax + By = 8' that contains the points (0, -9) and (-3, 0), we can use the two points to determine the slope (m) and then find the equation of the line.

The slope of the line through points (x1, y1) = (0, -9) and (x2, y2) = (-3, 0) is calculated as:

m = (y2 - y1) / (x2 - x1) = (0 - (-9)) / (-3 - 0) = 9 / -3 = -3

Now, using the slope-intercept form (y = mx + b), we can find 'b' (the y-intercept) when x=0:

y = -3x + b

Since the line passes through (0, -9), we substitute x=0 and y=-9:

-9 = -3(0) + b

b = -9

Therefore, the equation of the line is y = -3x - 9. Now we rearrange this to match the given form, Ax + By = 8:

3x + y = -9

Comparing this with Ax + By = 8, it's clear that B = 1, which is not one of the options provided. So there seems to be an error in the question as presented.

User CapelliC
by
8.8k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.