2x(x - 3) + 7(x - 3)
Can I have an explanation on how it works factors

Step-by-step explanation:

2x(x - 3) + 7(x - 3)

2x^2 - 6x + 7x - 21

reduce

2x^2 + x - 21

if this is equal to 0 then:

2x^2 + x - 21 = 0

factored:

(2x + 7)(x - 3) = 0

How that was done:

Divide the (2x^2) into (2x) and (x).

Divide the (-21) into (+7) and (-3). You choose these numbers so that their sum, when multiplied by (2x) and (-3), adds up to (+x).  

a)(x-2)^2+(y-1)^2=9

step-by-step explanation:

(picture explains)

lol.

it's ok we all do this sometimes.

-aparri