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:
10 ft to nearest foot.
Step-by-step explanation:
We use the Pythagoras theorem:
12^2 = 6^2 + h^2 where h is the height on the barn
h^2 = 12^2 - 6^2
h^2 = 144 - 36 = 102
h= √108 = 10.39
Let z = sin(x).
.. z^2 -2z = 2
.. z^2 -2z +1 = 3
.. (z -1)² = 3
.. z -1 = ±√3
.. z = 1 -√3 . . . . . the positive solution is extraneous
sin(x) = 1 -√3
Answer:
C. 3.3 kg.
Step-by-step explanation:
There are 1000 grams in a kilogram.
So 3,000 g = 3300/1000
= 3.3 kg.
Answer:
4 and 9 hundreths
Step-by-step explanation:
