a + b + 88 = 178 

a + b = 90

Mà a = b 

=> a = b = 45

vì 90 = 45 + 45

vậy: a = b = 45

a+b+88=178

a+b     = 178-88

a+b     =   90

Vì a=b nên a,b=45

k mik đi mik bạn rồi nhé

63 x 178 - 53 x 178

=178 x ( 63 - 53 )

=178 x 10

=1780

63 x178 - 53 x 178 = (63-53)x178 = 10 x178 = 1780 nha e , 100% đúng nha

a) 87 x (-78) + 78 x 31 - 78 x (-156)

= (-87 + 31 + 156) x 78

=  100 x 78

= 7800

b) -178 x (-35 - 78) - 78 x (178 + 35)

= -178 x (-113) - 78 x 213

= 20114 - 16614

= 3500

a) 1968 x 15 + 1968 x 84 + 1968

= 1968 x 15 + 1968 x 84 + 1968 x 1

= 1968 x (15 + 84 + 1)

= 1968 x 100 = 196800

b) 6412 + 5378 + 3582 + 4628

= (6412 + 5378) + (3582 + 4628)

= 11790 + 8210

= 20000

c) 178 x 101 - 178

= 178 x 101 - 178 x 1

= 178 x (101 - 1)

= 178 x 100

= 17800

d) 153 x 8 + 153 + 153

= 153 x 8 + 153 x 1 + 153 x 1

= 153 x (8 + 1 + 1)

= 153 x 10

= 1530

X x 27 - 178 = 15050

 X x 27          =15050+178

 X x 27           = 15228

 X                   = 15228 : 27

 X                  =   564

56 x 33= 1848

88 x 88= 7744

97 x 45= 4365

46 x 33= 1518

67 x 43= 2881

30 x 15= 450

28 . 178 - 14 . 2 . 79 + 7.4

⇒ 28 . 178 - 28 . 79 + 28 . 1

⇒ 28 . ( 178 - 79 + 1 )

⇒ 28 . 100

⇒ 2800

   28 \(\times\) 178 - 14 \(\times\) 2 \(\times\) 79 + 7 \(\times\) 4

= 28 \(\times\) 178 - 28 \(\times\) 79 + 28 \(\times\) 1

= 28 \(\times\) (178 - 79 + 1)

= 28 \(\times\) {(178 + 1) - 79)}

= 28 \(\times\) { 179 - 79}

= 28 \(\times\) 100

= 2800

\(-5x-178=14x+145\\ =>14x+5x=-178-145\\ =>19x=-323\\ =>x=-17\)

$-5x-178=14x+145$

$-19x=323$

$x=-17$