NCERT Exemplar Solutions
Class 6 - Mathematics - Unit 7: Algebra - Fill in the Blanks
Question 28

Question. 28

The solution of the equation 3x + 7 = –20 is _________.

Answer:

The solution of the equation 3x + 7 = –20 is –9.

Detailed Answer with Explanation:

  1. We want to find the value of (x) that makes the equation true.
  2. Start with: (3x + 7 = -20)
  3. Remove (+7) from the left by subtracting (7) on both sides:
    (3x + 7 - 7 = -20 - 7)
    (3x = -27)
  4. Now divide both sides by (3) to get (x) alone:
    ( rac{3x}{3} = rac{-27}{3})
    (x = -9)
  5. Check your answer: Substitute (x = -9) back into the left side:
    (3(-9) + 7 = -27 + 7 = -20). This matches the right side.
Open NCERT PDF