## anonymous one year ago linear equation 5a+11=a-13

1. anonymous

2. anonymous

So are we solving for a then?

3. anonymous

yes why do people keep saying that??

4. anonymous

Well it's always good to confirm what the OP is asking for. There are a lot of people on this site who ask their questions in a confusing way so I've just come to confirm at the start rather than later on lol

5. anonymous

kk

6. anonymous

Anyways, the way to go about solving this one would be to get all of the a values on one side and all of the number values on the other side.

7. anonymous

5a+a first right

8. anonymous

Well a is already positive on the right side, so to bring it over we would subtract it.

9. anonymous

In other words 5a-a

10. phi

you might think like this: how do I *get rid of a on the right side* ? answer: add -a but to keep things equal, you also add -a to the left side.

11. phi

ok but not just 4. it is 5 a's take away 1 a.

12. anonymous

open study whenever i get on its always acting wierd

13. anonymous

6a

14. phi

start over, and to it carefully 5a+11=a-13 add -a to both sides. what do you get? (and write out the whole equation)

15. anonymous

hold on one sec i need to draw it and it wont let me i'm going to refresh the page.

16. anonymous

|dw:1439758244788:dw|

17. phi

ok, except a+a is not 0 (it is 2a) try adding -a to both sides

18. anonymous

7a then.

19. phi

start over, 5a+11=a-13 add -a to both sides. Just write -a on both sides. can you do that ?

20. anonymous

21. anonymous

of how you would you do it

22. phi

yes, we will get the answer. I would add -a to both sides. that means write -a on both sides can you try to do that ?

23. anonymous

can you show me in drawing of how the step would be?

24. phi

you write -a on both sides , like this 5a+11 -a =a-13 - a

25. phi

if we look just at the "a" part , on the right side you have 1a take away 1 a on the left side you have 5 a's take away 1 a

26. anonymous

so its 4a?

27. phi

can you write out the whole equation? start with 5a+11 -a =a-13 - a and simplify both sides. can you do that ?

28. anonymous

yea sure one sec.

29. anonymous

5a+-a=a-13a ? is that what i would do on the right side

30. phi

you start with 5a+11 -a =a+ -13 + -a you can switch the order of the right side (if you want) to 5a+11 -a =a+ -a + -13 what is a+ -a ?

31. anonymous

2a?

32. phi

what is 1+ -1 ?

33. anonymous

0

34. phi

and 2+ -2 or 3+ -3 or a+ -a always adds up to 0

35. anonymous

kk

36. phi

5a+11 -a =a+ -a + -13 the right side, a+ -a is 0 so you get 5a + 11 -a = 0 + -13 0 + -13 is -13 , right?

37. anonymous

yes

38. phi

so far we figured out 5a + 11 -a = -13 now look at the left side. it says 5 a's and 11 and take away 1 a we can simplify 5 a's take away 1 a.

39. anonymous

4a

40. anonymous

no sorry 6a

41. phi

ok, but try to get in the habit of writing the whole equation 5 a's take away 1 a is 4 a"s (we write it 4a) what is the whole equation?

42. anonymous

so it is 4a?

43. phi

yes. if you had 5 cows and took away 1 cow, how many cows would you have? it works the same for a's

44. anonymous

4a+11=-13

45. phi

notice if you could make the 11 "go away" you would have 4a by itself luckily we can make 11 go away. we add -11 and we have to add -11 to the other side to keep things equal write -11 on both sides.

46. anonymous

then subtract 11to both sides 24 so then it would be 4a=-24

47. phi

yes. if we do it this way: 4a+11+-11=-13+-11 then on the left we have 11+-11 which is 0 (just like a+-a is zero) and on the right side -13 + -11 is -24 so you have 4a = -24 the last step is to divide both sides by 4 $\frac{4a}{4} = \frac{-24}{4}$

48. phi

it might not be obvious , by 4a/4 is just a

49. anonymous

-6 thanks

50. anonymous

a=-6

51. phi

yes. good job. if you do a bunch of these problems, it will start to make sense.

52. anonymous

thanks again. :)