Why do we make mistakes?

Because humans arent the brightest

how do you know your mistakes

If the value of x in the answer does not make the original equation true, then there’s a mistake somewhere. This means that checking whether or not your value of x makes the original equation true greatly reduces the frequency of mistakes on homework and tests.

how would you know about your mistake

You can find out if you made a mistake if your answer doesn't not make the original equation true.

This page has multiple problems - which one are you asking about? Please clarify your question if you need help.

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MAP Recommended Practice

Course: MAP Recommended Practice > Unit 17

Lesson 25: Finding mistakes in one-step equations

Finding mistakes in one-step equations

Google Classroom

Gain a deeper understanding of solving one-step equations by studying a correct and an incorrect example.

Solving one-step equations is all about using inverse operations on both sides of an equation to get the variable by itself. Answer the questions below to deepen your understanding of how to solve one-step equations.

Cam solved this problem $correctly$ ‍:

Solve for $x$ ‍:

\begin{aligned} 3 x & = 12 \\ \frac{3 x}{3} & = \frac{12}{3} \\ x & = 4 \end{aligned}

Why couldn't Cam just subtract $3$ ‍ to get the $x$ ‍ by itself?

(Choice A)
He could have!
(Choice B)
Because $3$ ‍ and $x$ ‍ are added together, and the inverse operation of addition is multiplication, not subtraction.
(Choice C)
Because $3$ ‍ and $x$ ‍ are multiplied together, and the inverse operation of multiplication is division, not subtraction.

Brooke solved this problem $incorrectly$ ‍:

Solve for $n$ ‍:

\begin{aligned} n + 4 & = 5 \\ n + 4 + 4 & = 5 + 4 \\ n & = 9 \end{aligned}

Why is Brooke's work incorrect?

(Choice A)
She should have been working to cancel out the $5$ ‍, not the $4$ ‍.
(Choice B)
$n$ ‍ and $4$ ‍ are added together, and the inverse operation of addition is subtraction. So, she should have subtracted $4$ ‍ from both sides instead of adding $4$ ‍ to both sides.
(Choice C)
$n$ ‍ and $4$ ‍ are added together, and the inverse operation of addition is division. So, she should have divided by $4$ ‍ on both sides instead of adding $4$ ‍ to both sides.

Solve a problem on your own

Solve for $k$ ‍:

k + 4.2 = 5.9

k =

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nelams.tedreaune
Posted 8 years ago. Direct link to nelams.tedreaune's post “how would you know the mi...”
how would you know the mistake
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- VioletF
  Posted 10 months ago. Direct link to VioletF's post “idk i got it wrong”
  idk i got it wrong
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Daren Huffer
Posted a year ago. Direct link to Daren Huffer's post “Why do we make mistakes?”
Why do we make mistakes?
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- desiderio.durgin
  Posted a year ago. Direct link to desiderio.durgin's post “Because humans arent the ...”
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taejonwalker
Posted 4 years ago. Direct link to taejonwalker's post “how do you know your mist...”
how do you know your mistakes
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- Ian Pulizzotto
  Posted 4 years ago. Direct link to Ian Pulizzotto's post “If the value of x in the ...”
  If the value of x in the answer does not make the original equation true, then there’s a mistake somewhere.
  
  This means that checking whether or not your value of x makes the original equation true greatly reduces the frequency of mistakes on homework and tests.
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  (17 votes)
gramspj
Posted 3 years ago. Direct link to gramspj's post “how would you know about ...”
how would you know about your mistake
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- Andrew H.
  Posted 2 years ago. Direct link to Andrew H.'s post “You can find out if you m...”
  You can find out if you made a mistake if your answer doesn't not make the original equation true.
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  (6 votes)
Kopano Mashala
Posted 3 months ago. Direct link to Kopano Mashala's post “k+4.2= 5.9, k is 1.7 righ...”
k+4.2= 5.9, k is 1.7 right, but how?
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- Godknight
  Posted 2 months ago. Direct link to Godknight's post “If the value of x in the ...”
  If the value of x in the answer does not make the original equation true, then there’s a mistake somewhere.
  
  This means that checking whether or not your value of x makes the original equation true greatly reduces the frequency of mistakes on homework and tests.
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  (1 vote)
Samaria k
Posted 2 years ago. Direct link to Samaria k's post “Why would u multiply”
Why would u multiply
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2012000951
Posted 2 years ago. Direct link to 2012000951's post “Later in algebra, you wil...”
Later in algebra, you will encounter two-step equations and then equations with more than two steps, including equations with parentheses and/or the variable on both sides. A strong understanding of one-step equations will help you solve multi-step equations later on.
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Kai Martin
Posted 6 months ago. Direct link to Kai Martin's post “a + 4 = 6 a + 4 - 4 = 6 ...”
a + 4 = 6

a + 4 - 4 = 6 - 4

a = 2

Is this correct? Why or why not?
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I am your question.
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Jana Wimer
Posted 2 years ago. Direct link to Jana Wimer's post “how did you know the answ...”
how did you know the answer
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- 26norejame
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