SOLUTION: Well im doing homework and i have the problem -5k-19=5-13k Well my teacher told us that you have to put the k's as one. We were doing a problem in class and she was showing a probl

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Question 106113: Well im doing homework and i have the problem -5k-19=5-13k Well my teacher told us that you have to put the k's as one. We were doing a problem in class and she was showing a problem where you would subtract one from another...like
-5k-13k but i thought you had to do the oppisite to where if in the equation it was subtracting you had to add? So if you could help i would really appiciate it.
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
-5k-19=5-13k
When you solve an equation, you have to move all of the known terms (numbers) on one side and all of the unknown (k) terms on the other.
Let's move all the k terms to the left hand side and all the non-k terms to the right hand side.
Remember, whatever you do to one side of the equation, you have to do to the other side of the equation.
-5k-19=5-13k
To get rid of the (-13k) on the right hand side, I have to add the additive inverse of (-13k).
The additive inverse of x is -x be because x+(-x)=0.
The additive inverse of (-13k) is -(-13k).
Negative times negative is positive or -(-13k)=13k.
Add 13k to both sides of the equation.
-5k-19=5-13k
-5k-19%2B13k=5cross%28-13k%29%2Bcross%2813k%29
-5k-19%2B13k=5
13k-5k-19=5
8k-19=5
To get rid of the -19 on the left hand side, use the additive inverse of -19.
The additive inverse of (-19) is -(-19) or (19).
Add 19 to both sides of the equation.
8k+%28cross%28-19%29%29%2Bcross%2819%29=5%2B19
8k=24
Now to get rid of the 8 in front of k, you need to use the multiplicative inverse of 8.
The multiplicative inverse of x is 1/x since x%2A%281%2Fx%29=1.
The multiplicative inverse of 8 is 1/8.
Multiply both sides of the equation by 1/8.
8k%2A1%2F8=24%2A1%2F8
%288%2F8%29k=24%2F8
k=3
Check your answer in your original equation.
-5k-19=5-13k
-5%283%29-19=5-13%283%29
-15-19=5-39
-34=-34
Good answer.
Since you get an answer that makes sense, your solution is good.
k=3.