SOLUTION: Please help me on factoring by grouping. 2x3 - 8x2 - 9x + 36

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Question 262784: Please help me on factoring by grouping.
2x3 - 8x2 - 9x + 36
Found 2 solutions by nerdybill, drk:
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
+2x%5E3+-+8x%5E2+-+9x+%2B+36
.
Group terms:
+%282x%5E3+-+8x%5E2%29+-+%289x+-+36%29+
.
Factor out what is common in each group:
+2x%5E2%28x+-+4%29+-+9%289x+-+4%29+
.
Factor out what is common for each term:
+%28x+-+4%29%282x%5E2+-+9%29+
.
You could stop there. However, you can consider factoring the second term as a the special case of "difference of squares":
+%28x+-+4%29%28sqrt%282%29x+-+3%29%28sqrt%282%29x+%2B+3%29+
.

Answer by drk(1908) About Me  (Show Source):
You can put this solution on YOUR website!
here is the original problem:
2x3+-+8x2+-+9x+%2B+36
step 1 - place (_) around the first and second pair of terms to get
%282x%5E3+-+8x%5E2%29+-+%289x+-+36%29
be careful here, we factored out a(-) from the second pair.
step 2 - find the GCF of both left and right (_) to get
2x%5E2%28x-4%29+-+9%28x-4%29
step 3 - find the GCF of the entire expression to get
%28x-4%29%282x%5E2-9%29