test tomorrow: simplify, classify poly's; solve quadratic eq

[kortness]

(Write in standard form and classify by degree and number of terms.)

(4x-5y) - (4x+7y)
-12y
constant monomial (is this correct or could the y count for the x and make it a *linear* monomial instead of a *constant* monomial?)

(Solve.)
64-x^3=0
(4-x) (16+4x+x^2)
x=-4,14,-18 (once more im not sure if i am doing this correctly)

 

[Deleted member 4993]

Re: Huge test tomorrow; need some help PLEASE

(Write in standard form and classify by degree and number of terms.)

(4x-5y) - (4x+7y)
= -12y<<<<<Correct - it is linear monomial - since it has a 'variable' and the power is '1'
constant monomial (is this correct or could the y count for the x and make it a *linear* monomial instead of a *constant* monomial?)

(Solve.)
64-x^3=0
(4-x) (16+4x+x^2)
x=-4,14,-18 (once more im not sure if i am doing this correctly)<<<<Incorrect - how did you get these numbers - show work

 

[kortness]

Re: Huge test tomorrow; need some help PLEASE

(Solve.)
64-x^3=0
(4-x) (x^2+4x+16) =0

4-x=0 -4 +or- sqrt.(4)^2-4(1)(16)
2(1)
-x=4
-4 + or - 32
x= - 4 2

-2 + or - 16
14, -18

 

[Deleted member 4993]

Re: Huge test tomorrow; need some help PLEASE

(Solve.)
64-x^3=0

(4-x) (x^2+4x+16) =0 

4-x=0             [u]-4 +or-   sqrt.(4)^2-4(1)(16)[/u]
                                        2(1)
-x=4<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< That is incorrect. It should be x = 4                          
                            [u]-4 + or - 32[/u]<<<<<<< what happened to the SQRT part  
x= - 4                                2
                                     
                               -2 + or - 16
                                    14, -18[/quote]