Question 123204: 3x+y<9 , the < or > signs means equal to or greater or lesser than.
x-y<7, the > has a line under it. Didn't know how to make it on here.
x>0,
Which of the following points satisfy the inequalities?
(2,5), ( 0,9), (3,-2) or (-1,0)
Answer by josmiceli(19441)   (Show Source):
You can put this solution on YOUR website! The best way is to plot these
(1) 
(2) 
(3) 
----------------
Find  in terms of 
(1)
(2)
multiply both sides by  and reverse the < sign
(3)  No involved here. This is saying that
can never be  or negative. It's domain is the right half of
the graph
I'll do a plot of
and
The solution is the little triangular area bounded by the axis
and the lines. Now see which points are in that area
-----------------
(2,5) looks to be just outside, and it fails (1) because
 This is clearly not true
------------------
(0,9) This looks like it might be in the area, but it fails (1) also
 This is clearly not true also
------------------
(3,-2) This fails in the area
------------------
(-1,0) can't be negative, as I said, and it is
also clearly outside the area
-------------------
So, only (3,-2) satisfies the inequalities answer
|
|
|
