Solve the problem.Robert has built a mechanical model solar system with three balls representing planets at the ends of rods attached to the center representing the sun. The planets are aligned when he turns on the motor. The innermost planet makes a revolution in 12 seconds, the middle planet makes a revolution in 20 seconds, and the outermost planet makes a revolution in 28 seconds. After how many seconds will the planets be aligned again?
A. 210 sec
B. 840 sec
C. 420 sec
D. 630 sec
Answer: C
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Graph the polar equation.r = - 
+ cos ?
A. 
B. 
C. 
D. 
Sketch the indicated curve. Find the intercepts. Find any asymptotes. Find any relative extrema and determine the intervals on which the curve is increasing and the intervals on which it is decreasing. Find any inflection points. Determine the intervals on which the curve is concave up and the intervals on which it is concave down.y = 
What will be an ideal response?
Solve the quadratic equation by the square root property. If possible, simplify radicals or rationalize denominators.y2 = 150
A. {5
}
B. {±6
}
C. {6
}
D. {±5
}
Find an equation of the line that satisfies the conditions. Write the equation in standard form.Through (2, 5); m = - 
A. 7x - 8y = 54 B. 8x + 7y = -54 C. 7x + 8y = 54 D. 7x + 8y = -54