Tangental Line
Level
pending
Two values of
m
will make the line
y = mx + b
tangent to the parabola
y = x² + 9
. Find the sum of the two numbers.
The answer is 0.
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1 solution
y = mx + b is the (or are the) tangential lines keeping b as a constant Y-intercept. Since the slope can be defined as the tan of angle between the line and the X axis, we have the following for the 2 slopes.
m1 + m2 = tan(x) + tan(180 - x) = m + (- m) = 0