The diameter of one circle is represented by 12x. The diameter of another circle is represented by 6x2y what is the ratio of the radiu of the two circles. 2:x3y 2x:y x:2y 2:xy

9514 1404 393

  (d)  2 : xy

Step-by-step explanation:

A common factor of 6x can be removed from the elements of the ratio. The ratio of radii is the same as the ratio of diameters.

  12x : 6x²y = (6x)(2) : (6x)(xy) = 2 : xy

x = ±sqrt(10)

step-by-step explanation:

5 - 2x² = -15

subtract 5 from each side

5-5 - 2x² = -15-5

-2x^2   = -20

divide by -2 on each side

-2x^2   /-2= -20/-2

x^2 =10

take the square root on each side

sqrt(x^2 )=±sqrt(10)

x = ±sqrt(10)

check:

5 - 2x² = -15

+sqrt(10)

5 - 2(sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15

-sqrt(10)

5 - 2(-sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15