Question

Will mark brainliest!

Answer 1

Answer:

b  =  −1

b  =  −4

Step-by-step explanation:

Common Factor

Divide both sides of the equation by the same term

Use the quadratic formula

Answer 2

Answer:

-1 or -4

Step-by-step explanation:

first all you have to do is to multiply 12 by 3b² to give you 36b² and then find a number(x) multiplied by another number(y) to give you 36b² and those two numbers must sum up to give you 15b

doing this, we would have our two numbers to be

12b and 3b

replace these two numbers with 15b in the equation

3b² + 12b + 3b + 12=0

(3b²+12b) + (3b+12)=0

3b(b+4)+3(b+4)=0

note: the numbers in the brackets must be the same

(3b+3)(b+4)=0

therefore, 3b + 3= 0 or b + 4= 0

3b+3= 0

3b=-3

b=-3/3

b=-1

or

b+4=0

b=-4