Q. Factor as the product of two binomials.x2−9x+20=
Identify quadratic trinomial: Identify the quadratic trinomial and its structure.The given expression is x2−9x+20, which is in the standard form of a quadratic trinomial ax2+bx+c, where a=1, b=−9, and c=20.
Determine factors of constant term: Determine the factors of the constant term c that add up to the coefficient b.We need to find two numbers that multiply to 20 (the constant term) and add up to −9 (the coefficient of x). The numbers that satisfy these conditions are −4 and −5, because (−4)×(−5)=20 and (−4)+(−5)=−9.
Rewrite middle term: Rewrite the middle term using the numbers found in Step 2.We can express −9x as the sum of −4x and −5x. Therefore, x2−9x+20 can be rewritten as x2−4x−5x+20.
Factor by grouping: Factor by grouping.We group the terms as follows: (x2−4x)+(−5x+20). Now we factor out the common factors from each group. From the first group, we can factor out an x, and from the second group, we can factor out a −5.This gives us x(x−4)−5(x−4).
Factor out common binomial factor: Factor out the common binomial factor.We notice that (x−4) is a common factor in both terms. We can factor this out to get (x−4)(x−5) as the final factored form of the expression.