Math help???

[KOPV]

hey everyone, if there is someone here willing to help, please do.. i'm doing homework with my gf and we are stuck on some problems.. we both are um! math challenged!?!?!?! lol..

Here are some problems we need help with.. its online, if anyone can help us answer it please do it would be greatly appreciated..


2.1 solve and check the fallowing equation

1) -[2z-(6z+6)]=6+(3z+4)


2) -[10z-(13z+4)]=4+(2z+2)


3) 0.12y+0.05(y+6000)=980


4) -.10(122)+0.90x=.05(x-6)


Help me out if you can Please!!!!!!

 

[edge003]

lol don't worry just copy the ones below

 

[MyLifeMJ]

here it is

1) -[2z - 6z - 6] = 6 + 3z +4
-[-4z - 6] = 10 + 3z
4z + 6 = 10 + 3z
4z - 3z = 10 - 6
z = 4

check : if we put 4 instead of z in the equation :
-[(2)(4) - (6(4) + 6)] = 6+(3(4) +4)
-[8 -(24 + 6)] = 6 + (12 + 4)
-[8 - 30] = 6 + 16
-(-22) = 22
22 = 22
we can see that both side of the equation are equal.

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

2) -[10z - 13z - 4 ] = 4 + 2z + 2
-[-3z - 4 ] = 6 +2z
3z + 4 = 6+ 2z
3z - 2z = 6 - 4
z= 2

check : if we put 2 instead of z in the equation :
-[10(2) - (13(2) + 4)] = 4 + (2(2) + 2)
- [20 - (26 + 4)] = 4 + (4 + 2)
- [20 - 30] = 4 + 6
- [-10] = 10
10 = 10
we can see that both side of the equation are equal.

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

3) 0.12y + 0.05y + (0.05)(6000) = 980
0.17y + 300 = 980
0.17y = 980 - 300
0.17y = 680
y = 680 / 0.17
y = 4000

check : if we put 4000 instead of y in the equation :
0.12(4000) + 0.05(4000 + 6000) = 980
480 + 0.05(10000) = 980
480 + 500 = 980
980 = 980
we can see that both side of the equation are equal.

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

4) -0.10(122) + 0.90x = 0.05(x-6)
12.2 + 0.90x = 0.05x - (0.05)(6)
12.2 + 0.90x = 0.05x - 0.3
0.90x - 0.05x = -0.3 - 12.2
0.85x = - 12.5
x = -12.5 / 0.85
x = - 14.7058823529411764....

check : if we put -14.705... instead of x in the equation :
-0.10(122) + 0.90(-14.705) = 0.05(-14.705-6)
12.2 - 13.2345 = 0.05(-20.705)
-1.0345 =~ -1.03525
we can see that both side of the equation are almost equal, we said "almost" because we put the aproximately value of the x.

good luck :cheeky:

i'm a statistician, so you can be sure about the solutions

 

[MyLifeMJ]

lol don't worry just copy the ones below

you're so kind, thank you :cheeky:

 

[Sharlene]

Did you really need to create another maths thread for another homework question? Also maybe you/your gf should look at getting tutored because this method obviously isn't helping yous learn

 

[KOPV]

^^ I couldnt find the old one to be honest..

and THANK YOU mylifemj, you are beautiful

 

[Sharlene]

^ For future reference: type 'math' in the advanced search for threads.

 

[N4ty]

:rofl: