125k views
5 votes
If the given expression 2x^2 + 5x - 12 is rewritten in the form (2x-3)(x+k), where k is a constant, what is the value of k?

a) k = 4
b) k = 3
c) k = -4
d) k = -3

User Pfych
by
8.7k points

1 Answer

6 votes

Final answer:

The value of k is obtained by factoring the quadratic expression 2x^2 + 5x - 12, where k corresponds to the number that satisfies the rewriting in the form (2x-3)(x+k). After factoring, k is found to be 4.

Step-by-step explanation:

If the given expression 2x^2 + 5x - 12 is rewritten in the form (2x-3)(x+k), where k is a constant, what is the value of k? To find the value of k, we need to factor the quadratic expression. We look for two numbers that multiply to (2 * -12) = -24 and add to the middle coefficient, which is 5. Those numbers are 8 and -3, because 8 * -3 = -24 and 8 - 3 = 5. By rewriting the expression as (2x^2 + 8x) + (-3x - 12) and grouping, we can rewrite the expression as 2x(x+4) - 3(x+4), which further simplifies to (2x - 3)(x + 4). Here, we see that the value of k is 4.

User Albarji
by
7.9k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories