M is proportional to the cube of r. when r=3m, m=216.when r=5 find the value of m

The value of m is 1000 for r=5

Step-by-step explanation:

Given that m is proportional to the cube of r

It can be written as:

When the proportionality symbol is removed a proportionality constant is introduced in the equation.

Let k be the proportionality constant

Given

r=3,m=216

Putting the values

The equation will now become

Putting r = 5

Hence,

The value of m is 1000 for r=5

2

step-by-step explanation:

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