Identify a, b, c: Identify a, b, and c in the quadratic expression 3n2+10n+7. Compare 3n2+10n+7 with the standard form ax2+bx+c. a=3b0b1
Find Numbers Multiply Add: Find two numbers that multiply to a∗c (which is 3∗7=21) and add up to b (which is 10).We need to find two numbers that satisfy these conditions.After checking possible pairs that multiply to 21 (such as 1 and 21, 3 and 7), we find that:1×21=213∗7=210This pair does not work since their sum is not 10.3∗7=2123∗7=213This pair works since their sum is 10.Two numbers: 3, 7
Rewrite Middle Term: Rewrite the middle term 10n using the two numbers found in Step 2.10n can be written as the sum of 3n and 7n.So, 3n2+10n+7 can be rewritten as 3n2+3n+7n+7.
Factor by Grouping: Factor by grouping.Group the first two terms and the last two terms:(3n2+3n)+(7n+7)Factor out the greatest common factor from each group:3n(n+1)+7(n+1)
Factor out Common Binomial: Factor out the common binomial factor (n+1). We now have 3n(n+1)+7(n+1), which can be factored as: (3n+7)(n+1)
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