Look at the function table.
X Y
-1 -8
0 -5
1 -2
2 1
What happens to y when x increases by 2?
A y decreases by 3
B y decreases by 6
C y increases by 3
D y increases by 6
The answer’s D…but I hav no clue why??
compare the y values when x changes from 0 (as in the pair (0,-5)) to 2 (as in the pair (2,1) when x increases by 2 (from 0 to 2), the y value increases from (-1) to 5: A difference of 6 in the positive direction.
February 6th, 2010 at 5:42 am
compare the y values when x changes from 0 (as in the pair (0,-5)) to 2 (as in the pair (2,1) when x increases by 2 (from 0 to 2), the y value increases from (-1) to 5: A difference of 6 in the positive direction.
References :
February 6th, 2010 at 6:02 am
y = 3x – 5
when x is increased by 2:
y = 3(x + 2) – 5
y = 3x + 6 – 5
y = 3x + 1
(3x +1) – (3x – 5)
= 3x + 1 – 3x + 5
= 6
That’s too long and tedious, here’s a short way:
dy / dx = 3
dy = 3 dx
dy = 3(2)
dy = 6
the fact that it’s positive indicates that it’s increasing, therefore y increases by 6.
References :
February 6th, 2010 at 6:35 am
Take a look at your table:
When x increases from -1 to 1, y increases from -8 to -2. That’s an increase of 6.
When x increases from 0 to 2, y increases from -5 to 1. That’s also an increase of 6.
You don’t have to know the equation. All you have to do is look at the data. The data tells you it increases by 6.
References :
February 6th, 2010 at 7:07 am
since x increses by 2, then the y will increase by 6
References :