Answer:
r represents the rate the electric company charges per kilowatt-hour.
Step-by-step explanation:
r represents the rate the electric company charges per kilowatt-hour.
Total charged to Zhao was 63.25 out of which 3.50 is administrative charge (fixed).
- Total charge consists of "administrative charge" + "charge per kilowatt hours*hours used
- The equation is given as 63.24 = 3.5 + 800r
<u>Matching the "word equation" with "mathematical equation", we see that 800 is the hours used and r is the charge per kilowatt hour.</u>
Answer: A.
Another way to solve by factoring 1/4.
![= [\dfrac{1}{4}(A + B)]^2](https://tex.z-dn.net/?f=%20%3D%20%5B%5Cdfrac%7B1%7D%7B4%7D%28A%20%2B%20B%29%5D%5E2%20)
Answer:
∠STU = 69°
Step-by-step explanation:
The angle with vertex T is called an "inscribed angle." It intercepts arc SU. The relationship you are asked to remember is that the measure of the inscribed angle (T) is half the measure of the arc SU.
Point V is taken to be the center of the circle. The angle with vertex V is called a "central angle." It also intercepts arc SU. The relationship you are asked to remember is that the measure of the central angle (V) is equal to the measure of arc SU.
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Using these two relationships together, we realize angle V is twice the measure of angle T:
∠SVU = 2×∠STU
18x +12° = 2(18x -57°) . . . . . . relationship between the marked angles
18x +12° = 36x -114° . . . . . eliminate parentheses
126° = 18x . . . . . . . . . . . add 114°-18x
∠STU = 18x -57° = 126° -57°
∠STU = 69°
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<em>Additional comment</em>
You may notice we did not solve for x. We only needed to know the value of 18x, so we stopped when we found that value. (Actually, we only need the value of 18x-57°. See below.)
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<em>Alternate solution</em>:
(18x +12°) -(18x -57°) = 18x -57° . . . . . . . subtract 18x -57° from both sides of the first equation.
69° = 18x -57° . . . . . simplify. This is the answer to the problem.
Umm. Is this high school?.
4 friends x 2 ballons = 8 friends only ballons.
8 + 1 = 9.
9 total
When you see the subtraction<span> (</span>minus<span>) sign followed by a </span>negative<span> sign, turn the two signs into a plus sign. Thus, instead of </span>subtracting<span> a </span>negative<span>, you're adding a </span>positive<span>, so you have a simple addition problem.</span>
