if one root of x^2+kx+12=0 may be triple of the other , then k is
Answers
Answer:
When factoring, we can use the method of FOIL which is First Outside Inside Last to check our factors. When I see a trinomial like this I say to myself….ok … x times x is x^2 so the First part of my factors is (x + )(x + ). Then I look at the 12. When I multiply the last two numbers in a binomial together the product is 12, so I need to find all the factors of 12……so 2 and 6; 3 and 4; 1 and 12. Which pair of factors meets the criteria that the second factor is 3 times the first factor? 2 times 3 = 6; 3 times 3 = 9; and 1 times 3 = 3…..ONLY the pair 2, 6 meet the criteria. So (x + 2)(x + 6) must be the two factors. Now to find the value of k, you must FOIL the two factors to find the middle value. First…..x times x = x^2; Outside….x times 6 = 6x; Inside 2 times x = 2x; Last……2 times 6 = 12.
So x^2 + 6x + 2x + 12 is what we get. We must combine like terms, and when we do; x^2 + 8x + 12 is what we get. Therefore, k = 8, or the coefficient of the x term.
Step-by-step explanation:
: k = 8
Answer:
then k=8
hope it's help you
