43.6k views
13 votes
Rewrite the expression by combining like terms.

3y + 5x2 + 10x + 2x2 + 15x - 3y
2 + 2xy + 2x
3x2 + 3x + 6y
7x24
30x² + 6y² + y

User Renm
by
3.6k points

1 Answer

7 votes

Answer:

Factoring 3x2 - 2x - 1

The first term is, 3x2 its coefficient is 3 .

The middle term is, -2x its coefficient is -2 .

The last term, "the constant", is -1

Step-1 : Multiply the coefficient of the first term by the constant 3 • -1 = -3

Step-2 : Find two factors of -3 whose sum equals the coefficient of the middle term, which is -2 .

-3 + 1 = -2 That's it

Step-3 : Rewrite the polynomial splitting the middle term using the two factors found in step 2 above, -3 and 1

3x2 - 3x + 1x - 1

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

3x • (x-1)

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

1 • (x-1)

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

(3x+1) • (x-1)

Which is the desired factorization

Final result :

5xy2 • (x - 1) • (3x + 1)

User Jrbjazz
by
3.6k points