polynomials?

Question

im having trouble with these kinds of problems
(2x2-3x+4)-(9x2+5x-6)
and the 2x2 and 9x2 is to the second power.

well actually its not 2x2 (two times two) but two to the second power. i hope its not confusing.

Answer 1

Is this equal to something? Usually, such equations are set up so you solve for x. What you listed is just a polynomial with no indication of solving for x (which is not really an equation since it's not equated to anything). What are you trying to do?

For future's reference, you'll be glad to know that the ^ symbol denotes power. So, your formula is:
(2x^2-3x+4) - (9x^2+5x-6)
I usually distribute the minus sign through:
2x^2-3x+4-9x^2-5x+6
Add like terms (x^2 with x^2, x with x, constant with constant):
-7x^2-8x+10

That is the final formula. Was it set equal to 0? If so, you can write it like:
-7x^2-8x+10=0
Multiply each side by -1 (it makes it nicer to write):
7x^2+8x-10=0
This is not easily factored out, so we use the quadratic formula. Using a=7, b=8, and c=-10, we get:
x=(-8+/-(344)^0.5)/14

Considering the complexity of the equation, I'm guessing you're just looking at just the function. Just keep in mind that you add and subtract like terms. x squared is added to x squared...not at all to just x.

Answer 2

do all the computations (the exponents) first, to make it look simpler. by the way, this ^ is how you write powers.
(2^2-3x+4) - (9^2+5x-6)
= (4-3x+4) - (81+5x-6)
= (8-3x) - (75+5x)
and remeber, when you open the secon parenthesis, because there's a minus sign in front of it, the signs of all the terms in the second parenthesis switch (i.e. from plus sign to minus sign, and vice versa)
(8-3x) - (75+5x)
= 8-3x-75-5x
= -8x-67

Answer 3

(2^2 -3x + 4)-(9^2 +5x -6) =

(4 - 3x + 4) - (81 +5x -6) =

(8 - 3x) - (75 + 5x) =

-67 - 8x

Answer 4

-67-8x(i did it wrong the first time)
this will be the right answer.

Answer 5

Ask your professor for help. That is what they are there for.