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Aline passes through (1,8) and is pependicular to the graph of y=2x+1. What question represents the line in slope-intercept forms?

User Clarkey
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1 Answer

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Two lines are perpendicular when the multiplication of their slopes is equal to -1.

The slope of the line: y = 2x + 1 is 2, then the slope of a perpendicular line will be:


\begin{gathered} m\cdot2=-1 \\ m=-(1)/(2) \end{gathered}

The slope-intercept form of a line is:

y = mx + b

where m is the slope, and b is the y-intercept.

Replacing into the equation with m = -1/2 and point (1, 8), we get:

8 = -1/2(1) + b

8 = -1/2 + b

8 + 1/2 = b

17/2 = b

Then, the equation is:

y = -1/2x + 17/2

User Matthew Gunn
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