53.[9-x]=53
Tìm x
A) (9.x-21) :3=2
B) (x - 39)-21=0
C) 231 +(312 -x)=531
D) 53.(9-x)=53
a, (9.x-21) : 3 = 2
=>9x-21=6
=>9x=27
=>x=3
b, (x-39)-21=0
=>x-39-21=0
=>x-60=0
=>x=60
c, 231+(312-x)=531
=>231+312-x=531
=>543-x=531
=>x=543-531
=>x=12
d, 53.(9-x)=53
=>9-x=1
=>x=8
a/ \(\frac{\left(9x-21\right)}{3}=2\)
\(\Rightarrow9x-21=2\cdot3=6\)
\(\Rightarrow9x=6+21=27\)
\(\Rightarrow x=\frac{27}{9}=3\)
b/ \(\left(x-39\right)-21=0\)
\(\Rightarrow x-39=0+21=21\)
\(\Rightarrow x=21+39=60\)
c/ \(231+\left(312-x\right)=531\)
\(\Rightarrow312-x=531-231=300\)
\(\Rightarrow x=312-300=12\)
d/ \(53\cdot\left(9-x\right)=53\)
\(\Rightarrow9-x=\frac{53}{53}=1\)
\(\Rightarrow x=9-1=8\)
a) ( 9 . x - 21 ) : 3 = 2
9 . x - 21 = 6
9 . x = 6 + 21
9 . x = 27
x = 27 : 9
x = 3
b) ( x - 39 ) - 21 = 0
x - 39 = 21
x = 21 + 39
x = 60
c) 231 + ( 312 - x ) = 531
312 - x = 531 - 231
312 - x = 300
x = 312 - 300
x = 12
d) 53 . ( 9 - x ) = 53
9 - x = 1
x = 9 - 1
x = 8
Đúng ghi Đ, sai ghi S:
a.53x (45 + 17)=53 x 45 + 53 x 17
b. 53+(45 x 17) = (53+45) x ( 53 + 17 )
c. ( 53 + 45 ) x 17 = 53x17 + 45x17
d. 53 + 45 x 17= 53 x 45 + 53 x 17
tính nhanh :
a, 53 + 8 + 53 + 53 c, ( 8 + 8 x 7 - 9 ) x ( 9 x 9 - 81 )
b, 24 x 2 x 2 + 2 x 12 x 6 d, ( 15 x 3 - 11 x 2 - 10 ) x ( 405 : 5 - 81 )
a, đáp án là :167 c,đáp án là :0
b, đáp án là : 240 d,đáp án là :0
Tính nhanh :
a, 53 + 8 + 53 + 53 c, ( 8 + 8 x 7 - 9 ) x ( 9 x 9 - 81 )
b, 24 x 2 x 2 + 2 x 12 x 6 d, ( 15 x 3 - 11 x 2 - 10 ) x ( 405 : 5 - 81 )
a.53 x 3 + 8 =167
b.24 x (2x2) + 2 x 12 x 6 = 240
c (8+56-9)x (81-81)
55x0
= 0
d (45-22-10)x(81-81)
=13 x 0
=0
Tính nhanh :
a, 53 + 8 + 53 + 53 c, ( 8 + 8 x 7 - 9 ) x ( 9 x 9 - 81 )
b , 24 x 2 x 2 + 2 x 12 x 6 d, ( 15 x 3 - 11 x 2 - 10 ) x ( 405 : 5 - 81 )
52(9-x)=53
`#3107`
`52(9 - x) = 52?`
`=> 9 - x = 52 \div 52`
`=> 9 - x = 1`
`=> x = 9 - 1`
`=> x = 8`
Vậy, `x = 8.`
\(52\left(9-x\right)=53\)
\(468-52x=53\)
\(52x=415\)
\(x=\dfrac{415}{52}\)
Vậy x = 415/52
#kễnh
\(52\left(9-x\right)=53\)
\(\Rightarrow9-x=\dfrac{53}{52}\)
\(\Rightarrow x=9-\dfrac{52}{53}\)
\(\Rightarrow x=\dfrac{425}{53}\)
1 tính nhanh c) 53(51 + 4 ) 53 ( 49 + 96) + 53 d) 3+6+9+12+....+123+126
c: =53*55+53*145+53
=53*201
=10653
d: Số số hạng là (126-3):3+1=42(số)
Tổng là (126+3)*42/2=2709
Tính hợp lý:
a, -3/4 + 3/7 + -1/4 + 4/9 + 4/7
b, -7/9 x 4/11 + -7/9 x 7/11 + 5 và 7/9
c, ( 21/31 + 2013/6039 ) - ( 44/53 - 10/31) - /53
a, -3/4 + 3/7 + -1/4 + 4/9 + 4/7
=\(\left(\frac{-3}{4}+\frac{-1}{4}\right)+\left(\frac{3}{7}+\frac{4}{7}\right)+\frac{4}{9}\)
=\(-1+1+\frac{4}{9}\)
=\(\frac{4}{9}\)
b, -7/9 x 4/11 + -7/9 x 7/11 + 5 và 7/9
\(=\frac{7}{9}x\frac{-4}{11}+\frac{7}{9}x\frac{-7}{11}+5x\frac{7}{9}\)
\(=\frac{7}{9}x\left(\frac{-4}{11}+\frac{-7}{11}+5\right)\)
\(=\frac{7}{9}x4\)
\(=\frac{28}{9}\)
c, ( 21/31 + 2013/6039 ) - ( 44/53 - 10/31) - /53
tính nhanh nhé
7) 53(51+4)+53(49+96)+53
8)42(15+96)+6(25+4).7
9) 45(13+78)+9(87+22).5
10) 16(27+75)+8(53+25).2
7)
53.(51+4)+53.(49+96)+53
=53.55+53.145+53
=53.(55+145+1)
=53.201
=10653
8)
42.(15+96)+6.(25+4).7
=42.111+(6.7).29
=42.111+42.29
=42.(111+29)
=42.140
=5880
9)
45.(13+78)+9.(87+22).5
=45.91+(9.5).109
=45.91+45.109
=45.(91+109)
=45.200
=9000
10)
16.(27+75)+8.(53+25).2
=16.102+(8.2).78
=16.102+16.78
=16.(102+78)
=16.180
=2880
7)
53.(51+4)+53.(49+96)+53
=53.55+53.145+53
=53.(55+145+1)
=53.201
=10653
8)
42.(15+96)+6.(25+4).7
=42.111+(6.7).29
=42.111+42.29
=42.(111+29)
=42.140
=5880
9)
45.(13+78)+9.(87+22).5
=45.91+(9.5).109
=45.91+45.109
=45.(91+109)
=45.200
=9000
10)
16.(27+75)+8.(53+25).2
=16.102+(8.2).78
=16.102+16.78
=16.(102+78)
=16.180
=2880