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 18 seconds, the middle planet makes a revolution in 30 seconds, and the outermost planet makes a revolution in 42 seconds. After how many seconds will the planets be aligned again?
A. 945 seconds
B. 630 seconds
C. 315 seconds
D. 1260 seconds
Answer: B
Mathematics
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Find all real roots of the given equation by using Newton's method.x = 
A. 0.7389836 B. -1 C. 0.7389836, -1 D. 0.7389816
Mathematics
Add or subtract.6
+ 8
A. 42
B. 14
C. 48
D. 14
Mathematics
Evaluate the expression for the given replacement values.2 + 2x - y
x = 4, y = -5
A. 20 B. 9 C. 15 D. 21
Mathematics
Determine whether the given sequence is arithmetic, geometric, or neither. If arithmetic, find the common difference. If geometric, find the common ratio.{3n2}
A. Geometric, r = 3
B. Geometric, r = 
C. Neither
D. Arithmetic, d = 3
Mathematics