SOLUTION: Determine which two equations represent perpendicular lines.
(1) y = 4x–6
(2) y = 1/4x+6
(3) y = –1/4x+6
(4) y = 1/4x–6
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-> SOLUTION: Determine which two equations represent perpendicular lines.
(1) y = 4x–6
(2) y = 1/4x+6
(3) y = –1/4x+6
(4) y = 1/4x–6
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You can put this solution on YOUR website! Since all equations are in the slope intercept form of y = mx + b where m is the slope
(it is the multiplier of x in the equation) and b is the value on the y-axis where the graph
crosses the y-axis.
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All you need to do for this problem is look at the multipliers of the x term.
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If the graphs are perpendicular, one slope must be plus and the other slope must be minus.
Not only that, but if one slope is N, the other slope must be 1/N for the lines to be perpendicular.
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In your answers, equation (3) is the only one that has a negative slope (that is a negative
multiplier of x). Therefore, this must be one of the equations. It's slope is:
.
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The other equation must have a positive slope. And since the slope of equation (3) is
of the form we are looking for an equation that has N as the slope.
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Notice that compares to in equation (3). So N must be 4. We are looking
for an equation that has a slope (multiplier of x) of +4. Equation (1) is the only one
that has +4 as the multiplier of x. So we can now say that the graphs of equations (1)
and (3) are perpendicular.
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Hope this helps you to understand the problem.
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