Recognize the structure: Recognize the structure of the quadratic expression.The given quadratic expression is in the form of ax2+bx+c, where a=5, b=22, and c=8.We need to find two numbers that multiply to ac (5×8=40) and add up to b (22).
Find two numbers: Find two numbers that multiply to 40 and add up to 22. The numbers that satisfy these conditions are 20 and 2 because 20×2=40 and 20+2=22.
Write middle term: Write the middle term of the quadratic expression as a sum of two terms using the numbers found in Step 2.5x2+22x+8 can be rewritten as 5x2+20x+2x+8.
Factor by grouping: Factor by grouping.Group the terms to factor out common factors:(5x2+20x)+(2x+8)5x(x+4)+2(x+4)
Factor out common binomial: Factor out the common binomial factor.Since both groups contain the binomial (x+4), we can factor it out:(5x+2)(x+4)
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