Solving first and second degree equations

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In summary, the conversation discusses solving two equations, one with a singular solution and one with two potential solutions. The correct solutions are provided, but it is noted that the math teacher made errors in the problem sheet. The person also mentions posting another algebra problem on a forum for help.
  • #1
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Homework Statement



solve the equations below


1.) 2x -1 = (1/2) *x +3

and

2) 1/x - 4/ x2= 0

Homework Equations


3. The Attempt at a Solution [/B]


2x -1 = 0,5x +3

2x= 0,5x +4
1,5x = 4
x= 4/ 1,5
x= 8/3

my math teacher told me that the x= 8/6 would have been correct solution to this first one



1/x -4/ x2 = 0

1/x = 4/x2

we enlarge the fraction 1/x

x/ x2 = 4/ x2

multiply both sides by x2

x= 4

singular solution assuming that originally x is unequal to 0 (because cannot divide with 0)

my teacher told me that this latter equation has twin solutions either x=-4 or x= 4

plugging -4 into the original equation, this seems not true at all...

-0,25 -( 0,25) = 0

-0,5 = 0

untrue.
 
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  • #2
late347 said:

Homework Statement



solve the equations below


1.) 2x -1 = (1/2) *x +3

and

2) 1/x - 4/ x2= 0

Homework Equations


3. The Attempt at a Solution [/B]


2x -1 = 0,5x +3

2x= 0,5x +4
1,5x = 4
x= 4/ 1,5
x= 8/3

my math teacher told me that the x= 8/6 would have been correct solution to this first one



1/x -4/ x2 = 0

1/x = 4/x2

we enlarge the fraction 1/x

x/ x2 = 4/ x2

multiply both sides by x2

x= 4

singular solution assuming that originally x is unequal to 0 (because cannot divide with 0)

my teacher told me that this latter equation has twin solutions either x=-4 or x= 4

plugging -4 into the original equation, this seems not true at all...

-0,25 -( 0,25) = 0

-0,5 = 0

untrue.
Your solutions are correct.
 
  • #3
ehild said:
Your solutions are correct.

Thank you for prompt response. It looks like even math teachers make silly mistakes sometimes. Twice in this problem sheet.

Can you take a gander at my other thread about algebra problem that I had. I just posted a simple word problem in the same precalculus homework math subrofum
 
  • #4
late347 said:
Thank you for prompt response. It looks like even math teachers make silly mistakes sometimes. Twice in this problem sheet.

Can you take a gander at my other thread about algebra problem that I had. I just posted a simple word problem in the same precalculus homework math subrofum
I see you solved it.
 
  • #5
Time to find another math teacher. :sorry: :rolleyes: :mad:
 

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