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Find the equation of the line perpendicular to 2x+5y=−21 that passes through the point (−8,1) in slope-intercept form. What is the correct equation for the line?

User Jhon
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1 Answer

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Final answer:

The equation of the line perpendicular to 2x+5y=-21 passing through (-8,1) is y=5/2x+21. This is found by calculating the negative reciprocal of the given line's slope and then using the point-slope form to determine the equation.

Step-by-step explanation:

To find the equation of the line perpendicular to 2x+5y=-21 that passes through the point (-8,1), we need to first find the slope of the given line.

The original equation can be rewritten in slope-intercept form (y=mx+b) as y=-(2/5)x-21/5. The slope (m) of this line is -2/5. For a line to be perpendicular, its slope must be the negative reciprocal of the original slope. Therefore, the slope of the perpendicular line is 5/2.

Using the point-slope form of a line equation, y-y1=m(x-x1), where (x1, y1) is the point (-8, 1) and m is the slope 5/2, we can write:

y-1=5/2(x+8).

Simplifying and putting it in slope-intercept form y=mx+b, we get:

y=5/2x + 21.

Therefore, the correct equation for the line is y=5/2x+21.

User Giovane
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