In the xy-plane, what is the y-intercept of line L?
(1) The slope of line L is 3 times its y-intercept?
(2) The x-intercept of line L is (-1/3)
Just a bit confused with x intercept,can somebody explain please?
thanks.
OA - E.
GPREP
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The general equation of a line is given by y=mx+c,where m is the slope and c is the y intercept
statement 1:
The slope of line L is 3 times its y-intercept
so m=3c
y=3cx+c
y=c(3x+1)
we cant determine c from this equation
Insufficient
statement 2:
The x-intercept of line L is (-1/3)
the x intercept of a line is obtained by evaluating x when y=0
0=m(-1/3)+c
m=3c
Value of c cannot be determined
Insufficient
combining the two statements we have
y=c(3x+1)
c=y/(3x+1)
m=3c
c=m/3
Value of c can still not be determined
So the ans is E..
statement 1:
The slope of line L is 3 times its y-intercept
so m=3c
y=3cx+c
y=c(3x+1)
we cant determine c from this equation
Insufficient
statement 2:
The x-intercept of line L is (-1/3)
the x intercept of a line is obtained by evaluating x when y=0
0=m(-1/3)+c
m=3c
Value of c cannot be determined
Insufficient
combining the two statements we have
y=c(3x+1)
c=y/(3x+1)
m=3c
c=m/3
Value of c can still not be determined
So the ans is E..