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Circle describe and correct each error 5r^2-6r=-15r^2-6r+1=0(R+1)(5r+1)=0R+1=0 and 5r+1=0R=-1 and b=1-/5

Circle describe and correct each error 5r^2-6r=-15r^2-6r+1=0(R+1)(5r+1)=0R+1=0 and-example-1
User EdXX
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1 Answer

24 votes
24 votes

Explanations:

Given the equation


5r^2-6r=-1

Add 1 to both sides


\begin{gathered} 5r^2-6r+1=-1+1 \\ 5r^2-6r+1=0 \end{gathered}

Factorize the result


\begin{gathered} 5r^2-5r-r+1=0 \\ 5r(r-1)-1(r-1)=0 \\ (r-1)(5r-1)=0 \end{gathered}

Error 1

According to the calculation in question, you can see that one of the errors made in the calculation is factorizing wrongly. The factors of the expression are (r-1) and (5r-1) instead of (r+1) and (5r+1)

Determine the zeros of the equation


\begin{gathered} (r-1)(5r-1)=0 \\ r-1=0\text{ and }5r-1=0 \\ r=1\text{ and }r=(1)/(5) \end{gathered}

Error 2:

The solutions shown in question are incorrect. The correct solution are 1 and 1/5

User Karel Maesen
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