Question

question
factor the trinomial:
$3x^2 + 25x + 28$
answer attempt 1 out of 2

Explanation:

Step1: Find product of leading & constant term

$3 \times 28 = 84$

Step2: Find pair summing to 25, product 84

The pair is 21 and 4, since $21+4=25$ and $21 \times 4=84$.

Step3: Split middle term using the pair

$3x^2 + 21x + 4x + 28$

Step4: Factor by grouping

$3x(x + 7) + 4(x + 7)$

Step5: Factor out common binomial

$(3x + 4)(x + 7)$

Answer:

$(3x + 4)(x + 7)$