Answer:
b=9 and b=-21
Step-by-step explanation:
first step: move 195 to the other side by adding to get:
b^2+12b=189
now to find the constant you take the b value which is 12 divide that by 2 and square it. then add the product to both sides. 12/2=6, 6^2=36
b^2+12b+36=189+36
next factor b^2+12b+36.
(b+6)^2=225
square root both sides to get:
b+6=15 and b+6=-15
solve by subracting 6 to both sides and you get the 2 final answers.
b=9 and b=-21