coord geo prob

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coord geo prob

by d0nw0ng » Sat Oct 06, 2007 11:51 am
in the xy-plan, the line equation ax + by + c = 0, where abc doesnt equal 0, has slope 2/3. what is b?

1) a=4
2) c= -6

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by samirpandeyit62 » Sun Oct 07, 2007 1:02 am
ax + by + c = 0

y=-a/b *x -c/b

stmt 1: a=4

now here -(a/b) =2/3 so b= -6 suff

stmt 2: c=-6,now at the x inetercept,

c/b = -a/b *x

so -6/b = -2/3*x
or
-6 =-a*x
now b can be anything depending upon a we cannot find its exact value
insuff

so ans should be A
Regards
Samir