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Write a slope-intercept equation for a line passing through the point (4, -2) that is parallel to the line 4x + 5y = 9. Then write a second

equation for a line passing through the point (4, - 2) that is perpendicular to the line 4x + 5y = 9

2 Answers

7 votes

Final answer:

To find the slope-intercept equation for a line parallel to 4x + 5y = 9 and passing through (4, -2), use the same slope and the point-slope form of a linear equation. The equation is y = (-4/5)x + 6/5. To find the slope-intercept equation for a line perpendicular to 4x + 5y = 9 and passing through (4, -2), use the negative reciprocal of the slope and the point-slope form. The equation is y = (5/4)x - 7.

Step-by-step explanation:

To find the slope-intercept equation for a line parallel to the line 4x + 5y = 9 and passing through the point (4, -2), we need to determine the slope of the given line. The slope-intercept form of a linear equation is y = mx + b, where m represents the slope and b represents the y-intercept. Since the line we want is parallel to 4x + 5y = 9, it will have the same slope. To find the slope of this line, we can rearrange the given equation into the slope-intercept form, y = mx + b.

4x + 5y = 9

5y = -4x + 9

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

So, the slope of the given line is -4/5. Now, we can use the point-slope form of a linear equation, (y - y1) = m(x - x1), to find the equation of the line passing through the point (4, -2).

(y - (-2)) = (-4/5)(x - 4)

y + 2 = (-4/5)x + 16/5

y = (-4/5)x + 16/5 - 2

y = (-4/5)x + 6/5

Therefore, the slope-intercept equation for the line parallel to 4x + 5y = 9 and passing through the point (4, -2) is y = (-4/5)x + 6/5.

To find the slope-intercept equation for a line perpendicular to the line 4x + 5y = 9 and passing through the point (4, -2), we need to determine the negative reciprocal of the slope of the given line. The negative reciprocal of -4/5 is 5/4. We can use the point-slope form of a linear equation again to find the equation of the line passing through (4, -2), but this time using the slope of 5/4.

(y - (-2)) = (5/4)(x - 4)

y + 2 = (5/4)x - 5

y = (5/4)x - 5 - 2

y = (5/4)x - 7

Therefore, the slope-intercept equation for the line perpendicular to 4x + 5y = 9 and passing through the point (4, -2) is y = (5/4)x - 7.

User Chris Lin
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Answer:

7y = -4 x + 8

y = -(4/7) x + /7

so m = -4/7

y = -(4/7)x + b

-2 = -(4/7)(4) + b

-14/7 + 16/7 = b

b = 2/7

so

y = -(4/7)x + 2/7

7y = -4x + 2

for the second one

m = -(-7/4) = 7/4

so

y = (7/4) x + b

now put x = 4 and y = 2 in again to find b

Step-by-step explanation:

User Tarun Behal
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3.9k points