Math is fun #1

1)

-8+(-4)-(-6)=					-4^2 =/= (-4)^2
-8-4+6=							-16 =/= 16
-12+6=
-6


2)

-4^2 - 2^3 =
-16-8=-24

A)

3-[-2(3-4)]+7=
3-[-2(-1)]+7=
10-2=8

_2_)

3a^2-2b^2-7a^2-3b^2=
-4a^2-5b^2


Solve for x:
4x-2(3x-7)=2x-6
4x-6x+14=2x-6
-2x+14=2x-6
___+6____+6
-2x+20=2x
+2x___+2x
_20_=_4x_
  4    4
5=x

-5x+25>=5`		Change the direction of the inequality after division or multiplication by a negative number.
___-25_-25
-5x>=-20
 -5   -5

x <= 4
   <-------*
 <--------------->
-∞ 0 1 2 3 4 5 6 ∞



Inequalities and the real number line

1) x>a 		       0---------->
	  <----------------------->
	  -∞           a        ∞
(a, ∞)

2) x<a	 <--------------0
	  <------------------------>
	 -∞	       a	   ∞
(-∞, a)

3) x>=a  	       *---------->
	  <----------------------->
	  -∞           a        ∞
[a, ∞)

4) x<=a   <-------------*
	  <------------------------>
	 -∞	       a	   ∞
(-∞, a]

5) a<x<b  	   0----------0
	  <----------------------->
	  -∞       a          b     ∞
(a. b)

6) a<=x<=b  	   *----------*
	  <----------------------->
	  -∞       a          b     ∞
[a, b]

7) a<x<=b  	   0----------*
	  <----------------------->
	  -∞       a          b     ∞
(a, b]

8) a<=x<b  	   *----------0
	  <----------------------->
	  -∞       a          b     ∞
[a, b)

Solve each of the following:

1) 3x-4>8

2) -2x+1>5

3) -5(x-1)<=10

For > and <, use 0 and parantheses ().
For >= and <=, use * and brackets [].

1/2x + 2/3 = 3/4, LCD=12
12(1/2x) + 12(3/4) = 12(3/4)
6x+8=9
  -8-8
6x=1
x=1/6



Solve the following as homework:

1) 5(x-6)=3(x+2)
2) (3n-1)/2 - (2n+3)/7 = 1
3) 5x-2 >= 4x-7
4) (n+4)/5 + (n-3)/6 >7/15
5) |2x+3|=4
6) |4x-1|=-3