21\25
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Answer:
90
Step-by-step explanation:
30x3=90
The answer is 36. because 12x3=36, 9x4=36, and 4x9=36, so it is the least common denominator
Answer: Raymond is correct
The DJ charges $75 an hour.
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Explanation:
x = number of hours
y = total cost
The DJ does a 3-hour event for $275. This means one point is (x,y) = (3,275)
Another point is (5,425) because a 5-hour event costs $425.
Let's find the slope of the line through these two points.

The slope is 75, meaning that each time y goes up by 75, x goes up by 1.
Flipped around it means each time x goes up by 1, y goes up by 75.
This means each time we add on an extra hour, the cost goes up by $75.
The DJ charges $75 an hour. Raymond is correct.
Answer:
Step-by-step explanation:
<em>Refer to attached picture</em>
- The height = h
- Angles of elevation 22.6° and 38.3°
- Closer distance = d
<u>Use tangent to solve</u>
- tan 22.6° = h/(d + 17) ⇒ h = (d + 17) tan 22.6° ⇒ h = 0.42(d + 17)
- tan 38.3° = h/d ⇒ h = d tan 38.3° ⇒ h = 0.79d
<u>Compare the equations above and find the value of d:</u>
- 0.42(d + 17) = 0.79d
- 0.42d + 7.14 = 0.79d
- 0.79d - 0.42d = 7.14
- 0.37 d = 7.14
- d = 7.14/0.37
- d = 19.3 m
<u>Now find the value of h:</u>
- h = 0.79d
- h = 0.79*19.3
- h = 15
Wave Rock is 15 m tall