1.

Factorise Y²+40Y+39​

Answer»

Answer:

1.1 Factoring y2-6y-40

The first term is, y2 its COEFFICIENT is 1 .

The middle term is, -6y its coefficient is -6 .

The last term, "the constant", is -40

Step-1 : Multiply the coefficient of the first term by the constant 1 • -40 = -40

Step-2 : Find two factors of -40 WHOSE sum equals the coefficient of the middle term, which is -6 .

-40 + 1 = -39

-20 + 2 = -18

-10 + 4 = -6 That's it

Step-3 : REWRITE the polynomial splitting the middle term using the two factors found in step 2 above, -10 and 4

y2 - 10y + 4y - 40

Step-4 : Add up the first 2 terms, pulling out like factors :

y • (y-10)

Add up the last 2 terms, pulling out common factors :

4 • (y-10)

Step-5 : Add up the four terms of step 4 :

(y+4) • (y-10)

Which is the desired factorization

Equation at the end of step

1

:

(y + 4) • (y - 10) = 0



Discussion

No Comment Found

Related InterviewSolutions