Question

The expression y2 – 10y + 24 has a factor of y – 4. What is another factor of y2 – 10y + 24? y – 20 y – 14 y – 8 y – 6

Answer 1

Just for future reference always put ^ for exponents. The answer is y-6 though. 
(y-4)(y-6) create that trinomial. You can prove that by using the FOIL algorithm 

Answer 2

Answer:

(y-6)

Step-by-step explanation:

$y^2 - 10y + 24$

We need to find out two factors whose product is 24 and sum is -10

-6  times -4 = 24

-6  +    -4 = -10

So two factors are -6  and -4

We write the factors inside the parenthesis

(y-6) (y-4)

Factor (y-4) is already given

So another factor is (y-6)