19.85
- 2.50
-------------
17.35
Answer: She'll pay $17.35 for the shirt.
38 < 4x + 3 +7 - 3x (original equation)
38 < 4x - 3x + 3 + 7 (combine like terms)
38 < x + 10 (simplify)
38 - 10 < x + 10 - 10 (subtract 10 from both sides to get (x) alone)
28 < x (simplify)
x > 28 (switch to get x on the left (its proper equation writing >.<) )
Given:
Q = 0.0764 kJ = 764 J, heat input
W = -830 J, useful work done
From the 1st Law of Thermodynamics, the change in internal energy is
δE = Q - W
= 764 - (-830)
= 1594 J = 1.594 kJ
Answer: 1.59 kJ (two sig. fig.)
The correct answer is choice D. If you put choice D into words, it is saying 30% (0.3) of the total is 12 minutes.
To solve this, use inverse operations.
<span><u>0.3m</u> = <u>12</u>
</span>0.3 0.3
m = 40
It will take Beck 40 minutes.
