Identify a, b, c: Identify a, b, and c in the quadratic expression 3x2−5x−2. Compare 3x2−5x−2 with ax2+bx+c. a=3b0b1
Find product and sum: Find two numbers whose product is a∗c (3∗−2=−6) and whose sum is b (−5).We need to find two numbers that multiply to −6 and add up to −5.The numbers −6 and 1 satisfy these conditions because:−6∗1=−6 (product)−6+1=−5 (sum)
Rewrite middle term: Rewrite the middle term −5x using the two numbers found in Step 2.3x2−5x−2 becomes 3x2−6x+x−2.
Factor by grouping: Factor by grouping.Group the terms: (3x2−6x)+(x−2).Factor out the common factors from each group.From the first group, factor out 3x: 3x(x−2).From the second group, factor out 1: 1(x−2).Now we have: 3x(x−2)+1(x−2).
Factor out common factor: Factor out the common binomial factor (x−2).The factored form is (3x+1)(x−2).