SOLUTION: Solve for n: S = n/2 (a + l) 2S = n (2a + 2l) 2S / 2 = 2an + 2ln / 2 S = an + ln How do I continue? Non-homework.

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Question 1086752: Solve for n:
S = n/2 (a + l)
2S = n (2a + 2l)
2S / 2 = 2an + 2ln / 2
S = an + ln
How do I continue? Non-homework.
Found 2 solutions by math_helper, MathTherapy:
Answer by math_helper(2461)   (Show Source): You can put this solution on YOUR website!
<<< Assuming this is what you intended for starting expression, same as S=(n/2)(a+l)
( Rearranged left and right sides, since we're solving for n let's write it on left. )
( Multiplied both sides by 2. )
( Divided both sides by a+l. Done. )
—

Your 2nd step above has an error: S = (n/2)(a+l) becomes 2S = n(a+l) after multiplying both sides by 2, not 2S=n(2a+2l).




——
7/5/17 - I corrected my last two steps, which had an error. Apologies for that.
7/8/17 - Meant to add that the domain restriction must accompany the answer.
Answer by MathTherapy(10552)   (Show Source): You can put this solution on YOUR website!
Solve for n:
S = n/2 (a + l)
2S = n (2a + 2l)
2S / 2 = 2an + 2ln / 2
S = an + ln
How do I continue? Non-homework.
 <===== l appears to be L, not 1, I guess



n(a + L) = 2S ------ Cross-multiplying



IGNORE all other RIDICULOUS answers!! 

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