SOLUTION: 4 + 3 |5n + 1| = 13 and 5 - 4 |2-3t| = 21

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Question 61778This question is from textbook
: 4 + 3 |5n + 1| = 13
and
5 - 4 |2-3t| = 21
This question is from textbook

Found 3 solutions by brandonpark2889, joyofmath, hotrodd:
Answer by brandonpark2889(31) About Me  (Show Source):
You can put this solution on YOUR website!
4 + 3 |5n + 1| = 13
and
5 - 4 |2-3t| = 21

2 problems?
Ok. First one: +4%2B3+%7C5n%2B1%7C=13. First, Always do the distributive prop ( if you don't know: a(b+c) = ab+ac). This case, 3 is the a. Always, multiply first. 3 x 5n = 15n. 3 x 1= 3. so it would be 4 + 15n + 3= 13. Now, add 4 and 3, which equals 7. After this, subtract 7 on each side: +15m+%2B+7+-+7+=+13+-+7+. What is left is 15m=6. Now, divide 15 on each side: 15m%2F15+=+6%2F15. Cancel out 15 on the first side, and 6/15 would be simplified to 2/5. m is 2/5.
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Second Problem: Same thing. Now, NEGATIVE 4 would be the a. Multiply -4 inside the absolute value, 2 and -3t. So, -4 x 2 is -8. -4 x -3t= 12t. So, what's left is 5 + -8 + 12t=21. 5-8 is -3. ADD 3 on each side: +-3+%2B+3+%2B+12t=+21+%2B+3 simplify: what is left is 12t=24. Divide 12 on each side: 12t%2F12=24%2F12. 24/12 is 2. So, t=2.
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Answer by joyofmath(189) About Me  (Show Source):
You can put this solution on YOUR website!
4 + 3 |5n + 1| = 13
Subtract 4 from both sides: 3 |5n + 1| = 9
Divide both sides by 3: |5n + 1| = 3
So, 5n+1 = 3 or 5n + 1 = -3
If 5n+1 = 3 then 5n=2 and n = 2/5
If 5n+1 = -3 then 5n=-4 and n = -4/5

5 - 4 |2-3t| = 21
Subtract 5 from both sides: -4 |2 - 3t| = 16
Divide both sides by -4: |2 - 3t| = -4
There's no solution because |2 - 3t|, by definition must be >= 0. It can never be -4.

Answer by hotrodd(18) About Me  (Show Source):
You can put this solution on YOUR website!
There are two answeres for each question.
Problem #1:
First, what we do is that we get everything that is not in the absolute value to the other side, so we subtract both sides by 4 and we divide eache side by 3, to get |5n + 1|=3. Because it is in absolute value, it can equal positive or negative 3. So we solve for positive 3 and then negative 3.
5n+1=3 subtract both sides by 1
5n=2 divide both sides by 5
n= 2/5
5n+1=-3 subtract both sides by 1
5n=-4 divide both sides by 5
n= -4/5
THE ANSWER IS: n= 2/5 and -4/5

Problem #2:
Simplify the equation like we did in problem #1. After doing that you should get the equation to look like |2-3t|= -4. But it is impossible to have the absolute value to be a negative so there isn't an answer. It is undefined.