Question 6 - Mind the Mistake, Mend the Mistake - Chapter 7 Class 7 - Finding the Unknown (Ganita Prakash II)

Transcript

Question 6 The following are some equations along with the steps used to solve them to find the value of the letter−number. Go through each solution and decide whether the steps are correct. If there is a mistake, describe the mistake, correct it and solve the equation.Is there a mistake? Yes What went wrong? The student divided by 3 too early. They divided the -12 by 3, but they didn't divide the +1 by 3. You can't do that! Correct solution Now, 3x + 1 = –12 Taking 1 on right side, it becomes subtraction 3x = –12 – 1 3x = – (12 + 1) 3x = –13 Taking 3 on right side, it becomes division x = (−𝟏𝟑)/𝟑