SOLUTION: 18. Question about this equation. y=-x^2-2x I have a table of values for x -3 -2 -1 0 1 When I have a negative number for x and the problem is already negative x, d

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: 18. Question about this equation. y=-x^2-2x I have a table of values for x -3 -2 -1 0 1 When I have a negative number for x and the problem is already negative x, d      Log On


   

Question 62389: 18. Question about this equation. y=-x^2-2x

I have a table of values for x
-3
-2
-1
0
1
When I have a negative number for x and the problem is already negative x, does that become a positive automatically? Hope I didn't confuse you with this question.
Found 2 solutions by stanbon, funmath:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
f(x)=-x^2-2x
I have a table of values for x
f(-3)=-(-3)^2-2(-3)=-9+6=-3
f(-2)=-(-2)^2-2(-2)=-4+4=0
f(-1)=-(-1)^2-2(-1)=-1+2=1
f(0)=0
f(1)=-1-2=-3
Cheers,
Stan H.

Answer by funmath(2933) About Me  (Show Source):
You can put this solution on YOUR website!
18. y=-x^2-2x

I have a table of values for x
-3
When x=-3 y=-%28-3%29%5E2-2%28-3%29
y=-%289%29%2B6
y=-3
-2
When x=-2 y=-%28-2%29%5E2-2%28-2%29
y=-%284%29%2B4
y=0
-1
When x=-1 y=-%28-1%29%5E2-2%28-1%29
y=-%281%29%2B2
y=1
0
When x=0 y=-%280%29%5E2-2%280%29
y=-0-0
y=0
1
When x=1 y=-%281%29%5E2-2%281%29
y=-%281%29-2
y=-3
:
I hope my demonastration answered your question. When you substitute numbers in for x, it helps to put them in parentheses to know what exactly your squaring and how your signs are effected.
Happy Calculating!!!