Mathematics

Mathematics

Problem

Two lines are perpendicular. If the slope of the first line is 45\dfrac{4}{5}, what is the slope of the second line? a) −45-\dfrac{4}{5} b) −54-\dfrac{5}{4} c) 54\dfrac{5}{4} d) −1-1
Intuitive explanation

When two lines are perpendicular, their slopes have a special relationship: they're negative reciprocals of each other. This means if one slope is ab\frac{a}{b}, the other is −ba-\frac{b}{a}. To find the perpendicular slope, flip the fraction and change the sign—this ensures the lines meet at a right angle.

Intuitive explanation

When two lines are perpendicular, their slopes have a special relationship: they're negative reciprocals of each other. This means if one slope is ab\frac{a}{b}, the other is −ba-\frac{b}{a}. To find the perpendicular slope, flip the fraction and change the sign—this ensures the lines meet at a right angle.

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