SOLUTION: Find the corresponding y values for x = -4, -3, -2, -1, 0, 1, 2 if y = x^2 + 2x- 3. help this is not sinking in at all.

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: Find the corresponding y values for x = -4, -3, -2, -1, 0, 1, 2 if y = x^2 + 2x- 3. help this is not sinking in at all.       Log On


   

Question 90405: Find the corresponding y values for x = -4, -3, -2, -1, 0, 1, 2 if y = x^2 + 2x- 3. help this is not sinking in at all.

Found 2 solutions by jim_thompson5910, stanbon:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Lets find the value of y when x=-4

y=x%5E2%2B2x-3 Start with the given polynomial


y=%28-4%29%5E2%2B2%28-4%29-3 Plug in x=-4


y=%2816%29%2B2%28-4%29-3 Raise -4 to the second power to get 16


y=%2816%29%2B-8-3 Multiply 2 by -4 to get -8


y=5 Now combine like terms
So when x=-4, y=5



----Now lets find another point----



Lets find the value of y when x=-3

y=x%5E2%2B2x-3 Start with the given polynomial


y=%28-3%29%5E2%2B2%28-3%29-3 Plug in x=-3


y=%289%29%2B2%28-3%29-3 Raise -3 to the second power to get 9


y=%289%29%2B-6-3 Multiply 2 by -3 to get -6


y=0 Now combine like terms
So when x=-3, y=0



----Now lets find another point----



Lets find the value of y when x=-2

y=x%5E2%2B2x-3 Start with the given polynomial


y=%28-2%29%5E2%2B2%28-2%29-3 Plug in x=-2


y=%284%29%2B2%28-2%29-3 Raise -2 to the second power to get 4


y=%284%29%2B-4-3 Multiply 2 by -2 to get -4


y=-3 Now combine like terms
So when x=-2, y=-3



----Now lets find another point----



Lets find the value of y when x=-1

y=x%5E2%2B2x-3 Start with the given polynomial


y=%28-1%29%5E2%2B2%28-1%29-3 Plug in x=-1


y=%281%29%2B2%28-1%29-3 Raise -1 to the second power to get 1


y=%281%29%2B-2-3 Multiply 2 by -1 to get -2


y=-4 Now combine like terms
So when x=-1, y=-4



----Now lets find another point----



Lets find the value of y when x=0

y=x%5E2%2B2x-3 Start with the given polynomial


y=%280%29%5E2%2B2%280%29-3 Plug in x=0


y=%280%29%2B2%280%29-3 Raise 0 to the second power to get 0


y=%280%29%2B0-3 Multiply 2 by 0 to get 0


y=3 Remove any zero terms
So when x=0, y=-3



----Now lets find another point----



Lets find the value of y when x=1

y=x%5E2%2B2x-3 Start with the given polynomial


y=%281%29%5E2%2B2%281%29-3 Plug in x=1


y=%281%29%2B2%281%29-3 Raise 1 to the second power to get 1


y=%281%29%2B2-3 Multiply 2 by 1 to get 2


y=0 Now combine like terms
So when x=1, y=0



----Now lets find another point----



Lets find the value of y when x=2

y=x%5E2%2B2x-3 Start with the given polynomial


y=%282%29%5E2%2B2%282%29-3 Plug in x=2


y=%284%29%2B2%282%29-3 Raise 2 to the second power to get 4


y=%284%29%2B4-3 Multiply 2 by 2 to get 4


y=5 Now combine like terms
So when x=2, y=5


Now lets make a table 





 xy



 -45
 

 -30
 

 -2-3
 

 -1-4
 

 0-3
 

 10
 

 25



Notice if we graph x%5E2%2B2x-3 and plot the points we found earlier, we see that the points lie on the curve. So this verifies our answer.

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Find the corresponding y values for x = -4, -3, -2, -1, 0, 1, 2 if y = x^2 + 2x- 3. help this is not sinking in at all.
-----------------
Just put each value of x in place of x in the formula.
For example
If x = -3, y = (-3)^2 + 2(-3) -1 = 9 - 6 -1 = 2
If x = 2, y = (2)^2 + 2*(2) - 3 = 4+4-3=5
etc.
Cheers,
Stan H.