Andrew M. answered • 03/24/16
Tutor
New to Wyzant
Mathematics - Algebra a Specialty / F.I.T. Grad - B.S. w/Honors
15 - 1/2b = -3
subtract 15 from both sides
-1/2b = -18
multiply both sides by 2b
-1 = -18(2b)
-1 = -36b
divide both sides by -36
-1/-36 = b
b = 1/36
David W.
PLZ note: Andrew does this so often, he thinks this is obvious:
To get "b" on one side of the equal sign (as in, "b="), you must do the opposite operations for a variety of operations. That is:
- where there is a +15, you do -15
- where there is times 1/2 ( or divide by 2), you divide by 1/2 (or multiply by 2)
- etc.
To "solve" means to find the value(s) of the variable that makes the equation true. So, it is a cool thing to check your answer --
Is 15 - 1/2b = -3 ?
15 - (1/2)(1/36) = -3 ?
15 - (1/72) = -3 ?
14 71/72 = -3 ?No
Actually, the answer is b=36. Everyone (I mean everyone!) makes mistakes, typos, etc. Get used to it. That's why checking (checking your own work and checking the work of others is important).
Now, you should have enough information to work this problem correctly.
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03/24/16
Joshua J.
Thank u
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03/24/16
David W.
p.s., I interpret " 1/2b " to mean " (1/2)b " not " 1/(2b) "
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03/24/16
Andrew M.
Now check the answer for 1/(2b) as the
problem was posted. I believe the answer
1/36 is correct for the problem as posted.
I interpreted it as it was put in. However,
if David is correct and it was intended to
be (1/2)b then, yes, the answer is 36.
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03/24/16
Tashaliah F.
dude thanks u helped alot
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03/26/21
Joshua J.
03/24/16