In the xy-plane, the line with equation ax+by+c=o, where abc doesn't equal 0, has slope 2/3. What is the value of b?
(1) a = 4
(2) c = -6
Please help and offer methods or strategies...
Thanks.
GMAT Prep Ques (Equation of line)
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- Morgoth
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dferm wrote:In the xy-plane, the line with equation ax+by+c=o, where abc doesn't equal 0, has slope 2/3. What is the value of b?
(1) a = 4
(2) c = -6
Please help and offer methods or strategies...
Thanks.
For equation ax+by+c=o
slope = -a/b
statement (1)
a=4
-a/b = 2/3
-4/b=2/3
b=-6
Sufficient.
Statement (2) It does not give us anything to work with.
Thus, A.
OA?
- Morgoth
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Answer has to be A, kindly check the OA.dferm wrote:How are you getting -a/b? I believe the answer to be E...
-a/b is a formula for slope
x intercept = -c/a
y- intercept = -c/b
Kindly refer the below link for further clarifications.
https://en.wikipedia.org/wiki/Slope
This is 750+ question.
it is definitely B.
any line will cross the X-ax if the slop is not zero.
A doesn't tell us anything about the slop
B tells us ab>0 hence neither a nor b equals zero. since -a/b is the slop of this line and since a is not zero, then the slop is not zero.
answer is B
it is definitely B.
any line will cross the X-ax if the slop is not zero.
A doesn't tell us anything about the slop
B tells us ab>0 hence neither a nor b equals zero. since -a/b is the slop of this line and since a is not zero, then the slop is not zero.
answer is B
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Rephrase ax + by + c = 0 in the form y=mx + b:dferm wrote:In the xy-plane, the line with equation ax+by+c=o, where abc doesn't equal 0, has slope 2/3. What is the value of b?
(1) a = 4
(2) c = -6
ax + by + c = 0
by = -ax - c
y = (-a/b)x - c/b.
The expression in blue represents the slope of the line.
Since the line has a slope of 2/3, we get:
-a/b = 2/3.
The determine the value of b, we need to know the value of a.
Question stem, rephrased:
What is the value of a?
Statement 1: a=4.
SUFFICIENT.
Statement 2: c=-6.
INSUFFICIENT.
The correct answer is A.
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
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