Question

factor completely.
$2x^2 - 17x + 21$

Explanation:

Step1: Find product of a and c

$2 \times 21 = 42$

Step2: Find factors of 42 summing to -17

$-3$ and $-14$

Step3: Split middle term

$2x^2 -14x -3x +21$

Step4: Factor by grouping

$2x(x -7) -3(x -7)$

Step5: Factor out common binomial

$(2x -3)(x -7)$

Answer:

$(2x - 3)(x - 7)$