Problem
\( 5 x^{2}+22 x+21 \)
Solution
Step 1 ：\( f(x) = 5x^{2} + 22x + 21 \)
Step 2 ：\( f(x) = (5x + 7)(x + 3) \)
Step 3 ：\( x = -\frac{7}{5}, -3 \)
Step 1 ：\( f(x) = 5x^{2} + 22x + 21 \)
Step 2 ：\( f(x) = (5x + 7)(x + 3) \)
Step 3 ：\( x = -\frac{7}{5}, -3 \)
