Posted by karan on Saturday, March 2, 2013 at 5:08am.
The slope of 2x-y=5 is 2
So the slope of a perpendicular line is -1/2
kx^2 + 10xy + 8y^2 = 0 is supposed to be the intersection of 2 straight lines, so let's solve it for y
y = (-10x ± √(100x^2 - 32kx^2) )/16
= (-10x ± x√100-68k)/16
= x(-10 ± √(100-32k) )/16
So the slope of the two lines is (-10 ± √(100-32k) )/16
thus:
(-10 ± √(100-32k) )/16 = -1/2
-20 ± 2√100-32k = -16
±2√100-32k = 4
±√100-32k = 2
square both sides
100-32k = 4
32k=96
k=3
check my arithmetic.
Related Questions
geometry - Martin drew a pair of perpendicular lines and a pair of parallel ...
Plz Check My Geometry - Out of 30 questions these few I struggled with. I put ...
Plz Check My Geometry - Out of 30 questions these few I struggled with. I put ...
Plz Check my Geometry(sOo0n) - 1.) Given points A(-4, 5), B(2, 3), C(0, 4) and D...
Geometry - Which best describes the relationship between the lines with ...
geometry - I'm stuck on this question please help. "Lines p and q ...
alg. - Determine which two equations represent perpendicular lines. a) y=2x - 6 ...
math help please - Tell whether the lines for each pair of equations are ...
calculus - f(x)=kx^2+3 a) if the tangent lines to the graph of f at (t,f(t)) and...
algebra - Is the following pair of lines paralle or perpendicular? Prove the ...
For Further Reading
