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lan solved the below problem He is confident his work is correct Checklar's work If he is correct, explain the work that he did. If he has made a mistake, idenufy his mistake and explain to lan host fint​

lan solved the below problem He is confident his work is correct Checklars work If he is correct explain the work that he did If he has made a mistake idenufy h class=

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mhanifa

Answer:

Correct steps given below:

  • 511 = -7 (10x - 13)
  • 511 = - 70x - (-91)
  • 511 = -70x + 91
  • -91             - 91
  • ---------------------
  • 420 = -70x
  • 420/-70 = -70x/-70
  • -6 = x

Ian missed the step 3 above.

He wrongly added 91 to both sides instead of subtracting, this resulted in wrong solution.

semsee45

Answer:

See below.

Step-by-step explanation:

The mistake Ian made was incorrectly distributing -(-91).  When multiplying two negative numbers the result is always positive:  [tex]-a \cdot -b=-a(-b)=ab[/tex].

This error meant he added 91 to both sides of the equation in Step 3 of his calculation, when he should subtract 91 from both sides.

Therefore, the correct calculation is:

[tex]\begin{array} { r l}511 & = -7(10x-13)\\\\511 & = -70x \phantom{)))}+91\\\\-91 & \phantom{))))))))))))} -91\\\\\cline{1-2}\\420 & = -70x\\\\\dfrac{420}{-70} & = \dfrac{-70x}{-70}\\\\-6 & = x\end{array}[/tex]

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