DS Coordinate Geometry
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Could someone please explain how both are sufficient in calculating the slope ..
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- jayhawk2001
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Let eqn of line n: y = m1x + c1
Eqn of line p: y = m2x + c2
1 - insufficient. we just have
1 = 5m1 + c1
1 = 5m2 + c2
2 - insufficient.
we just know c1 > c2
combining the two we can see that m2 > m1. Hence sufficient.
Eqn of line p: y = m2x + c2
1 - insufficient. we just have
1 = 5m1 + c1
1 = 5m2 + c2
2 - insufficient.
we just know c1 > c2
combining the two we can see that m2 > m1. Hence sufficient.
- logitech
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Multiply the first equation with -1 and add with the second equationjayhawk2001 wrote:Let eqn of line n: y = m1x + c1
Eqn of line p: y = m2x + c2
1 - insufficient. we just have
1 = 5m1 + c1
1 = 5m2 + c2
2 - insufficient.
we just know c1 > c2
combining the two we can see that m2 > m1. Hence sufficient.
-1 = -5m1-c1
1 = 5m2+c2
+
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0 = 5(m2-m1) + c2-c1
SO,
5(m2-m1) = c1-c2 from the second statement we know that c1>c2 so c1-c2>0
5(m2-m1) > 0
m2-m1 > 0
m2>m1
TATAMM!!
You can easily solve this question on XY plane without calculations.
LGTCH
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