Question

simplify -2(5x+y-5)+6(2x-2y+1)

Answer 1

do you know the "distributive law" ?

if you have -2 * ( 5x + y -5)
that means -2 times each term inside the parens

Answer 2

no i dont know the distribte law

Answer 3

do you know how to multiply -2 times 5x ?

Answer 4

yeah -10

Answer 5

what happened to the x ?

Answer 6

-10x
* sorry

Answer 7

so the idea is
-2 * ( 5x + y -5) can be written as -2* 5*x + -2 * y + -2 * -5
simplify (in algebra we don't bother to show the multiplication sign *)
you get
-10x -2y +10

now do the same for
+6(2x-2y+1)

Answer 8

ok thank you

Answer 9

what did you get ?

Answer 10

12x-12y+2

Answer 11

so you have changed
-2(5x+y-5)+6(2x-2y+1)

into
-10x -2y +10+ 12x-12y+2

to not get confused with subtractions, I write it as
-10x + -2y +10+ 12x + -12y + 2
now re-order them (we are adding so we can swap the order)
-10x +12x -2y + -12 y +10+ 2

Answer 12

-10x +12x + -2y + -12 y +10+ 2

notice you have 12 x's and take away 10 x's how many x's do you have?

can you simplify this?

Answer 13

2x

Answer 14

and how many y 's ?

Answer 15

10y

Answer 16

-2 y's and -12 y's is -14 y's or -14y

Answer 17

-14y

Answer 18

and finally +10+ 2

Answer 19

12

Answer 20

so -10x +12x -2y + -12 y +10+ 2
is
2x -14y +12

Answer 21

ok thank you so much

Answer 22

yw