Identify a, b, c: Identify a, b, and c in the quadratic expression 3u2+22u+7 by comparing it with the standard form ax2+bx+c. a=3 b=22 b0
Find numbers for ac: Find two numbers that multiply to a∗c (3×7=21) and add up to b (22).We need to find two numbers that satisfy these conditions.
Use numbers in expression: After trying different combinations, we find that the numbers 1 and 21 multiply to 21 and add up to 22.1×21=211+21=22
Rewrite middle term: Rewrite the middle term 22u using the two numbers found in the previous step.3u2+22u+7 can be rewritten as 3u2+1u+21u+7.
Factor by grouping: Factor by grouping. Group the first two terms together and the last two terms together.(3u2+1u)+(21u+7)
Factor out common factor: Factor out the greatest common factor from each group.u(3u+1)+7(3u+1)
Factor out common factor: Factor out the greatest common factor from each group.u(3u+1)+7(3u+1)Since both groups contain the common factor (3u+1), factor this out.(u+7)(3u+1)
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