OpenStudy (anonymous):

Please someone help me with this equation, I've been stuck on it for a while now. This is Subtracting polynomials. Subtract -4x^6+(-9x^2)+2x+(-8) from -8x^3+5x^2+3

6 years ago
OpenStudy (anonymous):

in subtracting polynomials, you'll have to subtract like terms. let's let P1 = -8x^3+5x^2+3 P2 = -4x^6+(-9x^2)+2x+(-8) you're question is P1 - P2 correct?

6 years ago
OpenStudy (anonymous):

Yes.

6 years ago
OpenStudy (anonymous):

I've done the equation around 6 times already and it keeps on telling me it's wrong.

6 years ago
OpenStudy (savvy):

always use parenthesis while subtraction..... (-8x^3 + 5x^2 + 3) - [-4x^6 + (-9x^2)+ 2x + (-8)] remember when there is a + sign outside the parenthesis open the parenthesis by keeping the sign of all the terms same as inside the parenthesis and whenever there is a - sign outside the parenthesis just change the sign of all the terms inside the parenthesis....

6 years ago
OpenStudy (savvy):

try it now....

6 years ago
OpenStudy (anonymous):

since there is no x^6 term in P1, you can think of it as 0x^6. So when we subtract P1 - P2 you'll have to take 0x^6 - (-4x^6) can you simplify this?

6 years ago
OpenStudy (savvy):

also....you can subtract like terms...

6 years ago
OpenStudy (anonymous):

Ii also tried with the parenthesis...

6 years ago
OpenStudy (anonymous):

actually, savvy's method is better..

6 years ago
OpenStudy (savvy):

see in continuity of my reply on parenthesis.... since before the first brackett there is no sign we keep signs of all the terms as it is, so it is: -8x^3 + 5x^2 + 3 and since there is a - sign outside the 2nd brackett we change all signs... 4x^6 - (-9x^2)- 2x - (-8) now also there are - signs outside some more bracketts so changing sins again would make it 4x^6 + 9x^2 - 2x + 8 now the expression becomes -8x^3 + 5x^2 + 3 + 4x^6 + 9x^2 - 2x + 8 now joining like terms which are only the constant terms and terms with x^2.... we get 4x^6 - 8x^3 + 13x^2 - 2x + 11

6 years ago
OpenStudy (anonymous):

It still says that the answer is wrong...

6 years ago
OpenStudy (campbell_st):

the problem is $-8x^3 +5x^2 + 3-(-4x^6 -9x^2+2x -8) = -8x^3 + 5x^2 + 3 + 4x^6 + 9x^2 -2x + 8$ which gives $4x^6 - 8x^3 + 14x^2 -2x +11$

6 years ago
OpenStudy (savvy):

oh yaah....i went wrong with that addition in the terms wid x^2.....lol..

6 years ago
OpenStudy (anonymous):

@__@ It's okay! Thanks everyone! Everyone deserves a medal!

6 years ago
OpenStudy (anonymous):

Can you guys help me with another one?

6 years ago