Question

−8x + 3y = 21 solve it

Answer 1

So first we have to subtract 3y from 21 cause the oppisit of addition which is subtraction so you get 18y when we divide that with -8y and get y=2.25y

Answer 2

-8x + 3y = 21
-8x + 8x + 3y = 21 + 8x
3y = 21 + 8x
 3          3
  y = 7 + 2 2/3x
-8x + 3(7 + 2 2/3x) = 21
-8x + 21 + 8x = 21
-8x + 8x + 21 = 21
0x + 21 = 21
0x + 21 - 21 = 21 - 21
0x = 0
 0     0
  x = 0
-8(0) + 3y = 21
0 + 3y = 21
3y = 21
 3      3
  y = 7
(x, y) = (0. 7)
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-8x + 3y = 21
-8x + 3y - 3y = 21 - 3y
-8x = 21 - 3y
 -8         -8
   x = -2 5/8 + 3/8y
-8(-2 5/8 + 3/8y) + 3y = 21
21 - 3y + 3y = 21
21 - 0y = 21
21 - 21 - 0y = 21 - 21
-0y = 0
 -0    -0
   y = 0
-8x + 3(0) = 21
-8x + 0 = 21
-8x = 21
 -8     -8
   x = -2 5/8
(x, y) = (-2 5/8, 0)