bài 3 : tim x các bạn làm từng phép tính nhé
10 + X = 12
X : 13 = 41
7 x X = 105
X – 29 = 31
192 – X = 129
( X – 34 ) : 15 = 0
320 – X : 4 = 8
250 – 50 x X = 100
( 40 – X ) – 7 = 18
124 + ( 118 – X ) = 217
156 – ( X + 61 ) = 82
( X – 35 ) – 120 = 15
Đáp án:
Giải thích các bước giải:
x+10=12
x=12-10
x=2
x:13=41
x=41×13
x=533
7xX =105
x=105:7
x=15
192-x=129
x=192-129
x=63
(x-34}:15=0
x-34=0x15
x-34=0
x=0+34
x=34
320-x:4=8
x:4=320-8
x:4=312
x=312×4
x=1248
250-50x X=100
50x X=250-100
50x X=150
x=150:50
x=3
(40-x}-7=18
40-x=18+7
40-x=25
x=40-25
x=15
124+(118-x}=217
118-x=217-124
118-x=93
x=118-93
x=25
156-(X+61}=82
x+61=156-82
x+61=74
x=74-61
x=13
(x-35}-120=15
x-35=15+120
x-35=135
x=135+35
x=170
$10 +x = 12$
$⇔ x = 12 – 10$
$⇔ x = 2$
Vậy $x=2$
$x : 13 = 41$
$⇔ x = 41 \times 13$
$⇔ x = 533$
Vậy $x=533$
$7 \times x = 105$
$⇔ x = 105 : 7$
$⇔ x = 15$
Vậy $x=15$
$x – 29 = 31$
$⇔ x = 31 + 29$
$⇔ x = 60$
Vậy $x=60$
$192 – x = 129$
$⇔ x = 192 – 129$
$⇔x = 63$
Vậy $x=63$
$( x – 34 ) : 15 = 0$
$⇔ x-34 = 0 \times 15$
$⇔ x-34 = 0$
$⇔ x = 0 + 34$
$⇔ x = 34$
Vậy $x=34$
$320 – x : 4 = 8$
$⇔ x: 4 = 320 – 8$
$⇔ x : 4 = 312$
$⇔ x = 312 \times 4$
$⇔ x = 1248$
Vậy $x=1248$
$250 – 50 \times x= 100$
$⇔ 50 \times x = 250 – 100$
$⇔ 50 \times x = 150$
$⇔ x = 150 : 50$
$⇔ x = 3$
Vậy $x=3$
$( 40 – x) – 7 = 18$
$⇔ 40-x = 18+7$
$⇔ 40-x = 25$
$⇔ x = 40 – 25$
$⇔ x = 15$
Vậy $x=15$
$124 + ( 118 – x) = 217$
$⇔ 118- x = 217 – 124$
$⇔ 118 – x = 93$
$⇔ x = 118 – 93$
$⇔ x = 25$
Vậy $x=25$
$156 – ( x + 61 ) = 82$
$⇔ x+61 = 156 – 82$
$⇔ x+ 61 = 74$
$⇔ x = 74 – 61$
$⇔ x = 13$
Vậy $x=13$
$(x – 35 ) – 120 = 15$
$⇔ x-35 = 15 + 120$
$⇔ x – 35 = 135$
$⇔ x = 135 + 35$
$⇔ x = 170$
Vậy $x=170$