Answer:
Step-by-step explanation:
Show that if 3x – 7 = 5, then x = 4.
Here, our given statement is 3x – 7 = 5, and we're asked to prove x = 4.
x=4
Statements Reasons
1. 3x – 7 = 5 Given
2. 3x – 7 + 7 = 5 + 7 Addition of 7 to equation (1)
3. 3x + 0 = 5 + 7 Substitution of –7 + 7 = 0 into (2)
4. 3x = 5 + 7 Substitution of 3x + 0 = 3x into (3)
5. 3x = 12 Substitution of 5 + 7 = 12 into (4)
6. 3x⁄3 = 12⁄3 Dividing equation (5) by 3
7. x = 12⁄3 Substitution of 3x⁄3 = x into (6)
8. x = 4 Substitution of 12⁄3 = 4 into (7)
Is there such a thing as being too descriptive? Yep, and that was it, since over half the proof was devoted to telling the reader how to do arithmetic. We'll typically take numerical computation for granted, and write proofs like this:
Answer:
1.39 × 10¹² or 1.39 × 10^12
Step-by-step explanation:
Yes he is correct because the 3 was in the tenths place. so say that the 3 is in the ones place multiply it by 10 and equales 3000. so you are just taking one zero with it