SOLUTION: How to solve 12b to the 2nd power = 27 + 27b

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Question 433492: How to solve 12b to the 2nd power = 27 + 27b
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
+12b%5E2=+27+%2B+27b
+12b%5E2+-+27b+-27=0......both sides divide by 3
+12b%5E2%2F3+-+27b%2F3+-27%2F3=0%2F3
+4b%5E2+-+9b+-9=0.....use quadratic formula
b=+%28-%28-9%29+%2B-+sqrt%28+%28-9%29%5E2-4%2A4%2A%28-9%29%29%29%2F%282%2A4%29+
b=+%289+%2B-+sqrt%2881-+%28-144%29%29%29%2F8+
b=+%289+%2B-+sqrt%2881%2B144%29%29%2F8+
b=+%289+%2B-+sqrt%28225%29%29%2F8+
b=+%289+%2B-+15%29%2F8+

b=+%289+%2B15%29%2F8+

b=+24%2F8+
b=+3.....one root

b=+%289+-15%29%2F8+

b=+-6%2F8+
b=+-0.75.....other root



+graph%28+600%2C+600%2C+-15%2C+15%2C+-45%2C+45%2C+12x%5E2-27x-27%29+