please help I just cant get the hang of these.
2006-12-15 10:39:40 · 16 answers · asked by momoftwins1986 1 in Science & Mathematics ➔ Mathematics
10 - 3x = -7x - 2
Your first step is to bring everything which has an x in it to the left hand side, and bring everything else to the right hand side. Our ultimate goal is to isolate x. I'll go through this one at a time with you.
10 - 3x = -7x - 2
First, we're going to bring the -7x to the left hand side. Remember that whenever we bring something to the other side, the sign changes. Thus, -7x is going to become +7x.
10 - 3x + 7x = -2
Now, let's bring the 10 over to the right hand side. Again, since it's positive 10, bringing it to the right hand side will make it negative.
-3x + 7x = -2 - 10
Now, we can combine like terms; that is, the terms that have an x in them, we can add normally as if the x weren't there. In this case, we're adding -3x and 7x, which is like adding -3 and 7, which is equal to 4, so combining them will give us 4x.
4x = -2 - 10
Now, we solve the right hand side, which is just straightforward arithmetic with integers.
4x = -12
Now, since we want to isolate x, what we want to do is divide both sides by 4. This will leave x by itself.
4x/4 = -12/4
Leaving us with
x = -3
The key thing to know is that this is an _equation_, meaning both of the sides have to be the same, and what you do to one side, you have to do to the other side.
2006-12-15 10:52:06 · answer #1 · answered by Puggy 7 · 1⤊ 0⤋
X=-3
2006-12-15 10:51:11 · answer #2 · answered by The "Dony" 3 · 1⤊ 0⤋
10 - 3x = - 7x - 2
10 - 3x + 3x = - 7x - 2 + 3x
10 = - 4x - 2
10 + 2 = - 4x - 2 + 2
12 = - 4x
12 /- 4 = -4 / - 4
- 3 = x
The answer is x = - 3
Insert the x value into the equation
- - - - - - - - - - - - - - - - - - - - - - -
Check
10 - 3x = - 7x - 2
10 - 3(- 3) = - 7(- 3) - 2
10 - (- 9) = -(- 21) - 2
10 + 9 = 21 - 2
19 = 19
- - - - - -s-
2006-12-15 11:01:10 · answer #3 · answered by SAMUEL D 7 · 0⤊ 0⤋
-3x+7x=4x, -10+-2= -12 x=-3
2006-12-15 10:51:28 · answer #4 · answered by Anonymous · 1⤊ 0⤋
10-3x=-7x-2 x=?
add like terms: 12= -4x
divide both sides by -4: -3=x
2006-12-15 10:43:10 · answer #5 · answered by !!!!!! 3 · 2⤊ 0⤋
10-3x=-7x-2 add 7
10+4x=-2 minus 10 from -2
4x=-12 divide by 4
x=-3 btw thats a negative
2006-12-15 10:42:01 · answer #6 · answered by ellizi 3 · 4⤊ 0⤋
General rule when solving equations: do the same operation to both sides in order to keep them equal. Now, in order to solve this equation for 'x' you must isolate 'x'. That is: get it on one side of the equal sign by itself. In order to do that start by subtracting 10 from each side.. that yields -3x=-7x-12. Now add 7x to each side.. that yields 4x=-12. Now divide each side by 4... that yields
x=-3. And that's the answer!!! Hope this helps.
2006-12-15 10:59:56 · answer #7 · answered by popcorn 3 · 1⤊ 0⤋
10-3x=-7x-2 (add 7 to both sides to cancel the -7 out)
10+4x=-2
4x=-12 (subtract 10 from both sides to cancel it out)
x=-3
2006-12-15 10:52:07 · answer #8 · answered by keeping it real 2 · 1⤊ 0⤋
10-3x=-7x-2
-3x + 7x = -2 -10
4x = -12
x = -12:4
x = -3
Solution: {x ER | x = -3}
<>>
2006-12-15 10:58:55 · answer #9 · answered by aeiou 7 · 1⤊ 0⤋
10-3x=-7x-2
10-4x=-2
-4x=12
x= -3
2006-12-16 03:30:00 · answer #10 · answered by ♥KiYa♥ 3 · 0⤊ 0⤋