Identify a, b, c: Identify a, b, and c in the quadratic expression 2f2+11f+9. Compare 2f2+11f+9 with ax2+bx+c. a=2b0b1
Find numbers multiply add: Find two numbers that multiply to a∗c (2∗9=18) and add up to b (11).We need to find two numbers that multiply to 18 and add up to 11.After checking possible pairs of factors of 18 (1 and 18, 2 and 2∗9=180, 2∗9=181 and 2∗9=182), we find that 2 and 2∗9=180 are the correct pair because 2∗9=185.
Rewrite middle term: Rewrite the middle term 11f using the two numbers found in Step 2.The expression 2f2+11f+9 can be rewritten by splitting the middle term into 2f and 9f.2f2+11f+9=2f2+2f+9f+9
Factor by grouping: Factor by grouping.First, group the terms: 2f2+2f + 9f+9.Now, factor out the common factors from each group.From the first group, factor out 2f: 2f(f+1).From the second group, factor out 9: 9(f+1).
Factor out common binomial: Factor out the common binomial (f+1). We have 2f(f+1)+9(f+1). Factor out the common binomial (f+1) to get (f+1)(2f+9).
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