Answer:
B. - 1/3
Step-by-step explanation:
(3b)³ = 3³·b³ = 27b³
x=21/5
5x:9 = 7:3
Turn the ratios into fractions:
5x/9 = 7/3
Then cross mutiply
15x=63
x = 10
Breaking down the equation
Simplification