SOLUTION: I am so lost in my math class right now and need help. I have a test tomorrow. We are working with Complex numbers, factoring and solving polynomial equations, solving quadratic e

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Question 365761: I am so lost in my math class right now and need help.
I have a test tomorrow. We are working with Complex numbers, factoring and solving polynomial equations, solving quadratic equations by finding the square root, Perfect square trinomials, and graphing quadratic functions,
Well I have a review worksheet and Im lost on a few things.
A) Factor the exression.
1. 121^2-25
my attempt. i got -3025 with 55times-55 but I dont think tats right.
B) Simplify the expression.
1. 3sqrt(8)times sqrt(18)
(I wasnt at school the day we learned this so I'm clueless)
c) solve the equation.
1. 3x^2-100=332
my attempt 3x^2-100=332
+100 +100
3x^2=sqrt(44)
sqrt(x^2)=sqrt(144)
x=12
My question is, is what method do I use to solve the equation?

D) perform the given operation.
1. 1-2i
----
3-5i
clueless on this one as well.
Sorry for the overload on problems. I'm just really confused.
If you could help me understand thatwould be great. Thanks
Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!

A) Factor the exression.
1. 121^2-25
my attempt. i got -3025 with 55times-55 but I dont think tats right. 

    121² - 25
    121² - 5²
(121 - 5)(121 + 5)   <--- that's factored

    (116)(126)
      14616

B) Simplify the expression.


 3sqrt%288%29sqrt%2818%29

 3sqrt%284%2A2%29sqrt%289%2A2%29
  
 3sqrt%284%29sqrt%282%29sqrt%289%29sqrt%282%29

 3%2A2%2Asqrt%282%29%2A3%2Asqrt%282%29
 
 3%2A2%2A3%2A%28sqrt%282%29%29%5E2

 3%2A2%2A3%2A2

 36

(I wasnt at school the day we learned this so I'm clueless)
c) solve the equation.
3x%5E2-100=332
3x%5E2+=+332%2B100
3x%5E2+=+432
x%5E2+=+144
x+=+%22%22+%2B-+sqrt%28144%29
x+=+%22%22+%2B-+12

My question is, is what method do I use to solve the equation? 


The principle of square roots.

----------------------------------

D) perform the given operation.


1-2i
----
3-5i 

multiply by the conjugate of the bottom over itself

1-2i  3+5i   3+5i-6i-10i²   3-i-10i²    3-i-10(-1)   3-i+10   13-i
----. ---- = ------------ = --------- = ---------- = ------ = ---- =  
3-5i  3+5i   9+5i-5i-25i²    9-25i²      9-25(-1)     9+25     34

13%2F34-expr%281%2F34%29i

Edwin