Question

Tolong bantu yang dilingkarin ya! Terimakasih.

Answer 1

4. -(x³ - 3x²y + 2xy² - 4y³) + ( -2x²y + 3xy² -5y³) - (-4x³ - xy² + 3y³ =
  = -x³ + 3x²y - 2xy² + 4y³ - 2x²y + 3xy² - 5y³ + 4x³ + xy² - 3y³
  = ( -x³ + 4x³) + (3x²y -2x²y ) + (-2xy² + 3xy² + xy²) + (4y³ - 3y³ - 5y³)
  = 3x³ + x²y + 2xy² -4y³

5. 18a - (-3a³ + 2a² - (4a - 13)) +7
   = 18a - ( - 3a³ + 2a² - 4a + 13) + 7
   = 18a + 3a³ - 2a² + 4a - 13 + 7
   = 3a³ - 2a² + (18a + 4a ) + (-13 + 7)
   = 3a³ - 2a² + 22a - 6

6. 5x + 4 + (-7x + 3 - (4y -1) + 5y)  + (x - 2y)
  = 5x + 4 + ( -7x + 3 - 4y + 1 + 5y) + x - 2y
  = 5x + 4 + ( - 7x + y + 4) + x - 2y
  = 5x + 4 - 7x + y + 4 + x - 2y
  = ( 5x - 7x + x) + ( y - 2y) + 8
  = - x - y + 8

7. 30 + 11abc + [23 - (4abc - 5) - (6 + 2abc - 5)]
  = 30 + 11abc + [ 23 - 4abc + 5 - 6 - 2abc + 5]
  = 30 + 11abc + [ 27 - 6abc ]
  = 30 + 11abc + 27 - 6abc
  = 5abc + 57

8. a + b - c - [b - ((a - c) - b) + c ]
   = a + b - c - [ b - ( a - c - b) + c]
   = a + b - c - [b -a + c + b + c]
   = a + b - c - [ 2b + 2c - a]
   = a + b - c - 2b - 2c + a
   = 2a - b - 3c

9. - [ + (- (+a - 1 ))] - (-(-(-1 -a )))
  = - [ -a + 1] + 1 - a
  = a - 1 + 1 -a
  = 0

10. - [ -a -(2a - (3a - 4))] - [5a + (-6a + (7a - 8))]
  = - [ -a - ( 2a - 3a + 4) ] - [ 5a + (-6a + 7a - 8)]
  = - [ -a -(-a + 4) ] - [ 5a +(-a -8)]
  = - [-a + a - 4 ] - [5a - a - 8]
  = -(-4) - (4a - 8)
  = 4 - 4a + 8
  = - 4a + 12

Answer 2

?? mata aku sampai kebalik loh.. enggak cuman keliru aja..