Identify coefficients: Identify the coefficients a, b, and c in the quadratic expression 2z2+9z+7 by comparing it to the standard form ax2+bx+c.a=2, b=9, c=7.
Find suitable numbers: Find two numbers that multiply to a∗c (2∗7=14) and add up to b (9).The numbers that satisfy these conditions are 2 and 7 because 2∗7=14 and 2+7=9.
Rewrite middle term: Rewrite the middle term, 9z, using the two numbers found in the previous step: 2z and 7z. The expression becomes 2z2+2z+7z+7.
Factor by grouping: Factor by grouping. Group the first two terms and the last two terms. 2z2+2z + 7z+7.
Factor out common factor: Factor out the greatest common factor from each group. 2z(z+1)+7(z+1).
Final factored form: Since both groups contain the common factor (z+1), factor it out.The factored form is (2z+7)(z+1).
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