Identify a, b, c: Identify a, b, and c in the quadratic expression 4u2+20u+25. Compare 4u2+20u+25 with ax2+bx+c. a=4b0b1
Find two numbers: Find two numbers whose product is a∗c (4∗25=100) and whose sum is b (20).We need to find two numbers that multiply to 100 and add up to 20.10∗10=10010+10=20Two numbers: 10, 10
Write quadratic expression: Write the quadratic expression using the two numbers found in Step 2.4u2+20u+25 can be written as 4u2+10u+10u+25.
Factor by grouping: Factor by grouping.Group the terms: (4u2+10u)+(10u+25).Factor out the common factors from each group.2u(2u+5)+5(2u+5).
Factor common binomial: Factor out the common binomial factor.The common binomial factor is (2u+5).The factored form is (2u+5)(2u+5) or (2u+5)2.