Respuesta :

choixongdong

Answer:

C. b = -5/3

Step-by-step explanation:

9b2 + 30b + 25 =0

(3b)^2 + 30b +(5)^2  = 0  <---perfect square

(3b + 5)^2 = 0

(3b + 5) = 0

3b = -5

 b = -5/3

Answer

C. b = -5/3

Answer:

C. b = -5/3

Step-by-step explanation:

9b² + 30b + 25 = 0

We can factor: two numbers that add up to 30 and its' product is 225: 15 & 15.

So we have 9b² + 15b + 15b + 25 = 0.

We can change this to (3b + 5) (3b + 5), or (3b + 5)².

This means there is only one solution: 3b + 5 = 0.

This can be turned into 3b = -5 -> b = -5/3.

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