Respuesta :

Answer:

-3(9x-7)

Step-by-step explanation:

first multiply

20x2=40  

and now its -40x+13x+21

then add same variables

-40x+13x=-27x

now its -27x+21

then rewrite the equation

3 x 7=21

-3 x 9x = 27x

now its (-3 x 9x) + (3 x 7)

then the multiply thingy and you got the answer