I need help with math homework ... 8th Grade Honors Algebra Review.?

Question

I don't remember how to simplify equations from 7th grade Pre-Alegebra.

I've always been in honors classes, so i just need a refresher.

here's the questions :

1.) 4x² - 3xy - 6x² + 8xy = ___

2.) 2(5x³ - 6x² - 4x) - 8(3x³ + 9x² - 3x) = ___

cann you help me ?

Answer 1

1. add the like terms ie. 4x² - 6x² = -2x²

                                   -3xy+8xy= 5xy

= -2x² +5xy.....its prob better 2 get rid of the minus infront of 2x²

-(-2x² +5xy)=2x² -5xy

2. 7x³-12x²  -8x-24x³ -72x²  +24x= -17x³-84x² +16x= 17x³+84x² -16x

Answer 2

combine your like terms

1.

the x^2 are like and the xy terms are like so

4x^2 - 6x^2 = -2x^2

and -3xy + 8xy = 5xy

keep the unlike terms in the answer

5xy-2x^2

2.

distribute

(10x^3)-(12x^2)-(8x)-(24x^3)-(72x^2)+(...

once agen combine your like terms

-14x^3  -84x^2  +16x

Answer 3

do you need to solve the equations for x and y? if you just need to simplify:

1) -2x^2 + 5xy

2)-14x^3 - 84 x^2 + 16x

Answer 4

you can only combine like terms:

1.) -2x^2 +5xy

2.) 10x^3 -12x^2 -8x -24x^3 -72x^2 +24x =

-14 x^3 - 84^2 +16x