Identify a, b, c: Identify a, b, and c in the quadratic expression 7f2+10f+3. Compare 7f2+10f+3 with the standard form ax2+bx+c. a=7b0b1
Find numbers multiply add: Find two numbers that multiply to a∗c (7∗3=21) and add up to b (10).We need to find two numbers that multiply to 21 and add up to 10.After checking possible pairs of factors of 21 (1 and 21, 3 and 7∗3=210), we find that 1 and 21 do not add up to 10, but 3 and 7∗3=210 do.So, the two numbers are 3 and 7∗3=210.
Rewrite middle term: Rewrite the middle term 10f using the two numbers found in Step 2.We can express 10f as 3f+7f.So, 7f2+10f+3 becomes 7f2+3f+7f+3.
Factor by grouping: Factor by grouping.Now we group the terms: 7f2+3f + 7f+3.Factor out the greatest common factor from each group.From 7f2+3f, we can factor out f, giving us f(7f+3).From 7f+3, we can factor out 1, giving us 1(7f+3).
Factor common binomial: Factor out the common binomial factor.We now have f(7f+3)+1(7f+3).The common binomial factor is (7f+3).Factoring out (7f+3) gives us (7f+3)(f+1).
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