# can someone teach me?

#### ctinnnna

##### New member
i'm having diffcult in these math problems! i couldn't understand what the
teacher was saying, and i couldn't even understand what she was doing..

solving equations:
1) p - 10 = -33
2) - 60 = -3f
3) y - (-22) = 50
4) 17 = k - (-8)
5) 2y - 1 = -7
6) -99 = -33 +g
7) 2h + (-2) = 18
8) 7z = -49

#### troublemaker676

##### Junior Member
For these types of equations you are solving for a variable, so to solve for the variable you must see what is happening to it and and do the oppsite, for example:

1) p - 10 = -33

the variable p was being subtracted by 10, now you must do the opposite, so add 10 to both sides of the equation, that gets your answer of -23

2) - 60 = -3f

Whats happening to the variable on this one? It is being multiplyed by -3, so do the opposite, divide both sides by -3, this gives you f=20, it should be positive though, a negative divided by a negative equals a positive.

See if you can do the rest.

Come back with a post reply if you need more help.

##### New member
um ok these r kind of easy, ill give you how to do a couple.

1)
ok so you have p-10 = -33
what you do to one side you have to do to the other so they balance out.
so if you add 10 to each side, then the result would be: p = -23
i see that your answers for 2 & 3 are incorrect, the answers would be, for 2) f = 20
3) y= 28
i hope my feeble attempts at teaching via compy will help you at least some

##### New member
oops, well looks like you have already gotten more competent help than i could give, alas i am too slow

:? :shock: :x :!:

#### ctinnnna

##### New member

oh, and how do you do this on the calculator to
check my answers -- if they are right or wrong?
or esle -- just tell me how to check my answers
without a calculator..

#### troublemaker676

##### Junior Member
I'm not quite sure what you mean by checking it on a calculator, but to check to see if your answers are right just put them back in for the variable in the equation and see if they work.

#### Unco

##### Senior Member
I have a thing against calculators performing algebra for students (particulary at this early stage), so I won't tell you how to use a graohics calculator to do the solving for you!

All you need to do for, say, the equation
2h + (-2) = 18
to check your answer of h=20 is plug h=20 in the left-hand side and check that it equals the right-hand side.

LHS = 2h + (-2)
LHS = 2*20 + (-2)
LHS = 40 - 2
LHS = 38

But RHS= 18
and 38 is not equal to 18.

So unfortunately we're off, and have to try again using the help in the above posts.

#### ctinnnna

##### New member
is this correct?

are these correct? and you don't have to check them all..

1) k + 16 = -20
2) c - (-21) = 40
3) -7t = -98
4) 3x - 7 = -19

and is this the right way?

-99= -33 + g
-99= + 33 g
do i subtract 99 - 33?

#### stapel

##### Super Moderator
Staff member
To check the solution to any "solving" problem, plug the value back into the original problem. If it "works", then the solution is likely valid.

Eliz.

#### troublemaker676

##### Junior Member
For that question you would add 33 to both sides, leaving you with g=-66, do not subtract 99 from 33. All the other ones look good!

#### ctinnnna

##### New member
//

thanks for helping me out!

just didn't get it because my teacher doesn't speak english
that well x] so i have no clue what she's talking about -- --;