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I failed algebra last year and now I'm doing an online class.

I forgot how to do these:

8 = |5y+2|

1>|2-0.8n|

|0.25y+1| = 0.5

You treat what is in the absolute value bracket as a negative and a positive and solve for both. So, pretend that the brackets are parens and put a - in front of one and + in front of the other.

8 = |5y+2| would be

8 = +(5y+2) and 8 = -(5y+2) which equals

8 = 5y+2 and 8 = -5y-2 now solve both for y

6=5y and 10 = -5y

y = 6/5 and y = -2

1>|2-0.8n| to solve inequalities, you change the greater or less than sign to =

1=(2-8/10n) 1= -(2-8/10n)

1=2-8/10n 1= -2+8/10n

-1 = -8/10n 3 = 8/10n

n = 10/8 n = 30/8

Inequalities take an extra step, now you need to determine if the answer is between the 2 solutions or less than and greater than. Pick a number between the two and see if the solution is true

1>|2- 8/10(9/8)|

1>|2 - 72/80| False, so try a number greater than 10/8, but less then 30/8

1>|2- 8/10(11/8)|

1>|2- 88/80| True statement, so n > 10/8 and less than 30/8, written as 10/8 < n < 30/8

You can check your work by substituting a number greater than 30/8 to confirm that n is between the two.

I'll leave the last one for you to practice on.

I can answer questions in basic algebra and any grade school math.

Love math, currently helping my nephew get through Intermediate Algebra.**Education/Credentials**

I majored in Math Ed in college (but decided not to teach), so have over 40 credits of math.