20 POINTS!! M is directly proportional to r squared when r=2, m=14
Workout the value of r when M =224

r = 8

Step-by-step explanation:

Given that M is directly proportional to r² then the equation relating them is

M = kr² ← k is the constant of proportionality

To find k use the condition when r = 2 , M = 14

k = =  =

M = r² ← equation of proportion

When M = 224, then

224 =r² ← multiply both sides by 2

7r² = 448 ( divide both sides by 7 )

r² = 64 ( take the square root of both sides )

r = = 8

have wonderful day

38.5

step-by-step explanation:

lets say, first number = r

second number = 3r+7

total = 49

(r)+(3r+7)= 49

4r+7 = 49

4r = 42

r = 42/4

r= 10.5

3r+7 = 3(10.5)+7 = 38.5

hope this

answer: 590

step-by-step explanation: