Answer:
(x+1)(2x+5)
Explanation:
f(x) = 2x² + 7x + 5
Factor the expression by grouping. First, the expression needs to be rewritten as 2x²+ax+bx+5. To find a and b, set up a system to be solved.
a+b=7
ab=2×5=10
Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. List all such integer pairs that give product 10.
1,10
2,5
Calculate the sum for each pair.
1+10=11
2+5=7
The solution is the pair that gives sum 7.
a=2
b=5
2x²+7x+5 as (2x²+2x)+(5x+5).
(2x²+2x)+(5x+5)
Factor out 2x in the first and 5 in the second group.
2x(x+1)+5(x+1)
Factor out common term x+1 by using distributive property.
(x+1)(2x+5)