Question

ALGUM EXPERT EM MATEMÁTICA EQUAÇÕES ME AJUDA URGENTEE ?? da 17 ate a 20 ??​

Answer 1

17)3x-21=3+x

3x+−21=3+x

3x−21−x=x+3−x

2x−21=3

2x−21+21=3+21

2x=24

2x/2 = 24/2

x = 12

18)−5x−6=36−8x

−5x+−6=36+−8x

−5x−6=−8x+36

−5x−6+8x=−8x+36+8x

3x−6=36

3x−6+6=36+6

3x=42

3x/3 = 42/3

x = 14

19)2x+31=43−10x

2x+31=43+−10x

2x+31=−10x+43

2x+31+10x=−10x+43+10x

12x+31=43

12x+31−31=43−31

12x=12

12x/12 = 12/12

x = 1

20)−3x−44=−39+2x

−3x+−44=−39+2x

−3x−44=2x−39

−3x−44−2x=2x−39−2x

−5x−44=−39

−5x−44+44=−39+44

−5x=5

-5x/-5 = 5/-5

x = -1