Question

(x²-4xy-221) factorise ​

Answer 1

Answer:

Factoring x2-4x-221

The first term is, x2 its coefficient is 1 .

The middle term is, -4x its coefficient is -4 .

The last term, "the constant", is -221

Step-1 : Multiply the coefficient of the first term by the constant 1 • -221 = -221

Step-2 : Find two factors of -221 whose sum equals the coefficient of the middle term, which is -4 .

-221 + 1 = -220

-17 + 13 = -4 That's it

Step-3 : Rewrite the polynomial splitting the middle term using the two factors found in step 2 above, -17 and 13

x2 - 17x + 13x - 221

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

x • (x-17)

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

13 • (x-17)

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

(x+13) • (x-17)

Which is the desired factorization