Math Help

Archive for May, 2006

Math Homework Solver App for iPhone/iPod

Question: odd math problem, please help me!?

I2xI + Ix+2I=3

Answer: first, note that for x<0, |2x|=-2x. for x>=0, |2x|=2x.
then, for x<-2, |x+2|=-(x+2) and for x>=-2, |x+2|=x+2

the above are results of the property of Absolute Value.

So, we can divide this into 5 sets:
If x<-2, x=-2, -20.

a) If x<-2, then |2x| = -2x (refer to above) and |x+2|= -x-2
So, -2x-x-2=3 =>-3x=5 => x=-5/3.
But, x=-5/3 isnt less than -2. so, no solutions.

b) if x=-2, we have 4=3. No solution

c) if -2 So, -2x+x+2=3 =>x=-1. and this is between -2 and 0. So x=-1

d) if x=0, 2=3, no solution

e) if x>0, |2x|=2x, |x+2|=x+2
So, 3x+2=3, x=1/3 and is greater than 0. so x=1/3

all in all, x=-1 and 1/3. hope this helps.:)

Algebra 2 – Using the Complement to Calculate Probability

Question: inequality graphing math?

Could someone help me with these inequality math problems and then graph them for me please… thanks..

Answer: Q1
-3x < -6
3x>6
x>2

x + 5 <= -2
x <= -7

Q2
x - 2 >= 2x + 1
-x >= 3
x <= -3

-10 > -2x -2
2x + 2 > 10
2x > 8
x > 4

how to graph here?

Math Calculations & Conversions : Graphing Inequalities With 2 Variables