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Question
Solve the following equation by trial and error method:
3m - 14 = 4
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Solution
Let m = 1
Therefore, 3m − 14
= 3 × 1 − 14
= 3 − 14
= −11
But, −11 ≠ 4
L.H.S. ≠ R.H.S.
Now, let's assume m = 2
Therefore, 3m − 14
= 3 × 2 − 14
= 6 − 14
= −8
But, −8 ≠ 4
L.H.S. ≠ R.H.S.
Now, let's assume m = 3
Therefore, 3m − 14
= 3 × 3 − 14
= 9 − 14
= −5
But, −5 ≠ 4
L.H.S. ≠ R.H.S.
Now, let's assume m = 4
= 12 − 14
= −2
But, −2 ≠ 4
L.H.S. ≠ R.H.S.
Now, let's assume m = 5
Therefore, 3m − 14
= 3 × 5 − 14
= 15 − 14
= 1
But, 1≠ 4
L.H.S. ≠ R.H.S.
Now, let's assume m = 6
Therefore, 3m − 14
= 3 × 6 − 14
= 18 − 14
= 4
Therefore, m = 6
L.H.S. = R.H.S.
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|
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|
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Complete the table and find the solution to the equation m − 7 = 3.
-
m
5
6
7
8
9
10
11
12
13
______
m − 7
______
______
______
______
______
______
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Solve the following riddles, you may yourself construct such riddles.
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| Who am I? |
 |
| I am a special number Take away from me a six! A whole cricket team You will still be able to fix! |
