-9(3-r)=45
-27+9t=45
9r=45+27
R=72/9
R=8
The answer is 8 not -8
Answer:
84
Step-by-step explanation:
In interval questions we use LCM
LCM of 7, 12=84
Therefore, the number of beats will pass before he again strikes them at the same time is 84
The Height of the ceiling at the center is 57.6628 feet
In geometry, an ellipse is a two-dimensional shape, that is defined along its axes. An ellipse is formed when a cone is intersected by a plane at an angle with respect to its base.
It has two focal points. The sum of the two distances to the focal point, for all the points in curve, is always constant.
The General form of ellipse is 
According to the question,
Length of whispering gallery is 130 feet
The foci are located 30feet from the center (0,0)
So, 2a = 130
=> a = 130/2
=> a = 65
and c = 30
As we know ,
=> c² = a² - b²
=> (30)² = (65)² - b²
=> 900 = 4225 - b²
=> b² = 4225 - 900
=> b² = 3325
=> b = 57.7 feet
Therefore , the height of the ceiling at the center is 57.6628 feet
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If angle "a" measures 42° the the other angles that will be congruent to angle "a" and also measure 42° will be angle d, angle e and angle h .
In the question ,
a figure is given ,
From the figure we can see that 2 parallel lines are cut by a transversal .
So ,
angle a = angle d .......because vertically opposite angles .
angle a = angle e ...because corresponding angles are equal in measure
also
angle e = angle h .... because vertically opposite angles .
Therefore , If angle "a" measures 42° the the other angles that will be congruent to angle "a" and also measure 42° will be angle d, angle e and angle h , the correct option is (a) .
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