60 + 40 + x = 101
a) 37.24 + 37.76 + 63.79 + 21.63
b) 101 + (-60) + 29 + (-40)
c) 40 + (139 – 172 + 99) – (139 + 199 – 127)
d) (158.129 – 158.39):180
a) 37.24 + 37.76 + 63.79 + 21.63
b) 101 + (-60) + 29 + (-40)
c) 40 + (139 – 172 + 99) – (139 + 199 – 127)
d) (158.129 – 158.39):180
giúp mình với ạ
a) 37.24+37.76+63.79+21.63
= 37(24+76)+63(79+21)
= 37.100+63.100
= (37+63)100
= 100.100
= 10000
b) 101+(-60)+29+(-40)
= (101+29)+(-60-40)
= 130-100
= 30
c) 40+(139-172+99)-(139+199-127)
= 40+139-172+99-139-199+127
= (139-139)+(-127+127)+(99-199)+40
= 0+0-100+40
= -60
d) (158.129-158.39):180
= [158(129-39)]:180
= (150.90):180
= 75
=
Bài 1 (2 điểm): Thực hiện phép tính
a) 37.24 + 37.76 + 63.79 + 21.63
b) 101 + (-60) + 29 + (-40)
c) 40 + (139 – 172 + 99) – (139 + 199 – 127)
d) (158.129 – 158.39):180
dài vậy ngại làm lắm t chỉ làm câu a , b thôi nha
g) 101 + (–60) + 29 + (–40)
h) 167 + (–252) + 52 + (–67) i) 38 – 138 + 250 – 350
k) 118 + 107 – (118 – 93) – 50 m) 40 + (139 – 172 + 99) – (139 + 199 – 172)
\(g,101+\left(-60\right)+29+\left(-40\right)=41+29+\left(-40\right)=70+\left(-40\right)=30\)
\(h,167+\left(-252\right)+52+\left(-67\right)=\left(-85\right)+52+\left(-67\right)=\left(-33\right)+\left(-67\right)=-100\)
\(i,38-138+250-350=\left(-100\right)+250-350=150-350=-200\)
\(k,118+107-\left(118-93\right)-50=225-25-50=100-50=50\)
\(m,40+\left(139-172+99\right)-\left(139+199-172\right)=40+\left[\left(-33\right)+99\right]-\left(338-172\right)\)
\(=40+66-166=106-166=-60\)
a) 19 . 25 + 19 . 16 + 41
b) (-8) . 72 + 8 . (-19)- (-8)
c) 28 +(19 - 28 ) - ( 32 - 57)
d) 101 + (- 60) + 29 + (- 40)
Giải các phương trình sau:
9) x-49/ 50 + x-50/ 49 = 49/ x-50 + 50/ x-49
7) x+25/ 75 + x+30/70 = x+35/65 + x+40/60
8) 99-x/101 + 97-x/103 + 95-x/105 + 93-x/107 = 4
10) x+14/86 + x+15/85 + x+16/84 + x+17/83 + x+116/4 = 0
7) \(\frac{x+25}{75}+\frac{x+30}{70}=\frac{x+35}{65}+\frac{x+40}{60}\)
\(\Leftrightarrow\)\(\frac{x+25}{75}+1+\frac{x+30}{70}+1=\frac{x+36}{65}+1+\frac{x+40}{60}+1\)
\(\Leftrightarrow\)\(\frac{x+100}{75}+\frac{x+100}{70}=\frac{x+100}{65}+\frac{x+100}{60}\)
\(\Leftrightarrow\)\(\left(x+100\right)\left(\frac{1}{75}+\frac{1}{70}-\frac{1}{65}-\frac{1}{60}\right)=0\)
\(\Leftrightarrow\)\(x+100=0\) (vì 1/75 + 1/70 - 1/65 - 1/60 \(\ne\)0)
\(\Leftrightarrow\)\(x=-100\)
Vậy.....
Giải các phương trình sau:
9) x-49/ 50 + x-50/ 49 = 49/ x-50 + 50/ x-49
7) x+25/ 75 + x+30/70 = x+35/65 + x+40/60
8) 99-x/101 + 97-x/103 + 95-x/105 + 93-x/107 = 4
10) x+14/86 + x+15/85 + x+16/84 + x+17/83 + x+116/4 = 0
7) \(\frac{x+25}{75}+\frac{x+30}{70}=\frac{x+35}{65}+\frac{x+40}{60}\)
\(\Leftrightarrow\)\(\frac{x+25}{75}+1+\frac{x+30}{70}+1=\frac{x+35}{65}+1+\frac{x+40}{60}+1\)
\(\Leftrightarrow\)\(\frac{x+100}{75}+\frac{x+100}{70}=\frac{x+100}{65}+\frac{x+100}{60}\)
\(\Leftrightarrow\)\(\left(x+100\right)\left(\frac{1}{75}+\frac{1}{70}-\frac{1}{65}-\frac{1}{60}\right)=0\)
\(\Leftrightarrow\)\(x+100=0\) (1/75 + 1/70 - 1/65 - 1/60 \(\ne\)0)
\(\Leftrightarrow\)\(x=-100\)
Vậy...
Tìm x
A:101=101.0x
X30=(1030x)40
A:101=101×0x
A:101=101×0
A:101=0
A. =0×101
A =0
Vậy A=0
Giải các phương trình sau:
9) x-49/ 50 + x-50/ 49 = 49/ x-50 + 50/ x-49
7) x+25/ 75 + x+30/70 = x+35/65 + x+40/60
8) 99-x/101 + 97-x/103 + 95-x/105 + 93-x/107 = 4
10) x+14/86 + x+15/85 + x+16/84 + x+17/83 + x+116/4 = 0
9: \(\dfrac{x-49}{50}+\dfrac{x-50}{49}=\dfrac{49}{x-50}+\dfrac{50}{x-49}\)
=>x-99=0
hay x=99
7: \(\Leftrightarrow\left(\dfrac{x+25}{75}+1\right)+\left(\dfrac{x+30}{70}+1\right)=\left(\dfrac{x+35}{65}+1\right)+\left(\dfrac{x+40}{60}+1\right)\)
=>x+100=0
hay x=-100
8:
Sửa đề: \(\dfrac{99-x}{101}+\dfrac{97-x}{103}+\dfrac{95-x}{105}+\dfrac{93-x}{107}=-4\)
\(\Leftrightarrow\left(\dfrac{99-x}{101}+1\right)+\left(\dfrac{97-x}{103}+1\right)+\left(\dfrac{95-x}{105}+1\right)+\left(\dfrac{93-x}{107}+1\right)=0\)
=>200-x=0
hay x=200