tìm x :
a) 219 - 7 ( x + 1 ) = 100
b) (3x - 6 ) . 3 = 34
219 – 7(x + 1) = 100 ; b) (3x - 6).3 = 34
a)
219-7(x+1)=100
=>7(x+1)=219-100
=>7(x+1)=119
=>x+1=119:7
=>x+1=17
=>x=16
A) 7(X+1)=219-100
7(x+1)=119
x+1=17
x=17+1
x=18
b)3x.6=54:3
3x.6=18
3x=18:6
3x=3
x=3:3
x=1
xin loi to nham = 16
Tìm số tự nhiên x, biết a) 219 – 7(x + 1) =100; b) (3x – 6).3 = 3/4
a)
<=> 219 - 7x - 7 = 100
<=> -7x = 100 - 219 + 7
<=> -7x = -112
<=> x = -112 : (-7)
<=> x = 16
b)
<=> 9x - 18 = 34
<=> 9x = 34 + 18
<=> 9x = 52
<=> x = 52 : 9
<=> x = 52/9
a)219-7(x+1)=100
7(x+1)=219-100
7(x+1)=119
x+1 =119:7
x+1 =17
x =17-1
x =16
b) (3x-6).3=34
3x-6 =34:3
3x-6 =\(\frac{34}{3}\)
3x =\(\frac{34}{3}\)- 6
3x =\(\frac{16}{3}\)
x =\(\frac{16}{3}\): 3
x =\(\frac{16}{9}\)
tìm số tự nhiên x biết
a,219-7(x+1)=100
b,(3x-6)*3=64
a)219-7(x+1)=100
7(x+1)=219-100
x+1=119/7
x+1=17
x=17-1
x=16
b)(3x-6)*3=64
3x-6=64/3
3x=64/3+6
3x=82/3
x=82/3:3
x=82/9
a) 219-7(x+1)=100
219-7x-7=100
-7x=100-219+7
-7x=-112
x=16
b) (3x-6).3=64
3x-6=64/3
3x=82/3
x=82/9
bài 13: tìm x biết
a. 124 + (118 - x) = 217
b. 156- (x + 61) = 82
c. 219 - 7(x + 1) = 100
d. (3x - 6). 3 = 3^4
e. 231 - (x - 6) = 1339 : 13
a) 124 + (118 - x) = 217
118 - x = 217 - 124
118 - x = 93
x = 118 - 93
x = 25
b) 156 - (x + 61) = 82
x + 61 = 156 - 82
x + 61 = 74
x = 74 - 61
x = 13
c) 219 - 7(x + 1) = 100
7(x + 1) = 219 - 100
7(x + 1) = 119
x + 1 = 119 : 7
x + 1 = 17
x = 17 - 1
x = 16
d) (3x - 6).3 = 3⁴
3x - 6 = 3⁴ : 3
3x - 6 = 3³
3x - 6 = 27
3x = 27 + 6
3x = 33
x = 33 : 3
x = 11
e) 231 - (x - 6) = 1339 : 13
231 - (x - 6) = 103
x - 6 = 231 - 103
x - 6 = 128
x = 128 + 6
x = 134
a) 124 + (118 - x) = 217
118 - x = 217 - 124
118 - x = 93
x = 118 - 93
x = 25
b) 156 - (x + 61) = 82
x + 61 = 156 - 82
x + 61 = 74
x = 74 - 61
x = 13
c) 219 - 7(x + 1) = 100
7(x + 1) = 219 - 100
7(x + 1) = 119
x + 1 = 119 : 7
x + 1 = 17
x = 17 - 1
x = 16
d) (3x - 6) . 3 = 34
(3x - 6) . 3 = 81
(3x - 6) = 81 : 3
(3x - 6) = 27
3x = 27 + 6
3x = 33
x = 33 : 3
x = 11
e) 231 - (x - 6) = 1339 : 13
231 - (x - 6) = 103
(x - 6) = 231 - 103
x - 6 = 128
x = 128 + 6
x = 134
cô cấm dùng máy tính -)
lớp 9 ms đc dùng:_)
giúp mình 2 bài tìm x này với:
a) 219 - 7 (x + 1) = 100
b) (3x - 6) x 3 = 3^4
a/ => 7(x + 1) = 119
=> x + 1 = 17
=> x = 16
b/ => 3x - 6 = 33 = 27
=> 3x = 33
=> x = 11
tìm số tự nhiên x, biết:
a) 219-7(x+1)= 100 b) (3x-6) . 3= 3 mũ 4
a)219-7(x+1)=100
7(x+1)=219-100
7(x+1)=119
x+1=119:7
x+1=17
x=17-1
x=16
b)(3x-6).3=34
(3x-6).3=81
3x-6=81:3
3x-6=17
3x=27+6
3x=33
x=33:3
x=11
li-ke cho mình nha Duong Thi Hoai My
nếu gì nguyện cau chúc củat bai t0an va thay s0 thi sa0
Tìm số tự nhiên x, biêt:
a, 219 - 7(x + 1) = 100
b, (3x - 6) . 3 = 34
a)
\(219-7\left(x+1\right)=100\)
\(\Rightarrow7\left(x+1\right)=119\)
\(\Rightarrow x+1=17\)
=> x = 16
Vậy x = 16
b)
\(\left(3x-6\right)3=3^4\)
\(\Rightarrow\left(x-2\right)3^2=3^4\)
=> x - 2 = 9
=> x = 7
Vậy x = 7
Giải:
a, 219 - 7(x + 1) = 100
7(x + 1) = 219 - 100
7(x + 1) = 119
x + 1 = 119 : 7
x + 1 = 17
x = 17 - 1
x = 16
b, (3x - 6) . 3 = 34
(3x - 6) . 3 = 81
3x - 6 = 81 : 3
3x - 6 = 27
3x = 27 + 6
3x = 33
x = 33 : 3
x = 11
Tìm số tự nhiên x, biết:
a. 219 - 7(x+1) = 100
b. (3x - 6) . 3 = 34
a. 219 - 7(x+1) = 100
7(x+1)=119
x+1=119:7
x+1=17
x=16
Vậy x=16
b. (3x - 6) . 3 = 34
3x-6=34:3
3x-6=33
3x=33
x=11
Vậy x=11
a) \(219-7\left(x+1\right)=100\)
\(\Leftrightarrow219-7x-7=100\)
\(\Leftrightarrow-7x=100-219+7=-112\)
\(\Leftrightarrow x=16\)
b) \(\left(3x-6\right)\cdot3=3^4\)
\(\Leftrightarrow\left(x-2\right)\cdot3^2=3^4\)
\(\Leftrightarrow x-2=3^2\)
\(\Leftrightarrow x=9+2=11\)
a) \(219-7\left(x+1\right)=100\)
\(\Rightarrow7\left(x+1\right)=119\)
\(\Rightarrow x+1=119:7\)
\(\Rightarrow x+1=17\)
\(\Rightarrow x=16\)
b) \(\left(3x-6\right)3=3^4\)
\(\Rightarrow\left(3x-6\right)=3^3:3\)
\(\Rightarrow\left(3x-6\right)=3^3\)
\(\Rightarrow\left(3x-6\right)=27\)
\(\Rightarrow3x=27-6\)
\(\Rightarrow3x=21\)
\(x=21:3\)
\(\Rightarrow x=7\)
Bài 1: Tìm x, biết .
a. 5x( 12x + 7) - 3x ( 20x - 5) = -100
b. 5x( 2x - 7) + 2x ( 8 - 5x) = 5
a)\(60x^2+35x-60x^2+15x=100\)
35x+15x=100
50x=100 =>x=2
b)\(10x^2-35x+16x-10x^2=5\)
-35x+16x=5
-19x=5 =>x=-5/19
a)60x2+35x−60x2+15x=10060x2+35x−60x2+15x=100
35x+15x=100
50x=100
=>x=2
b)10x2−35x+16x−10x2=510x2−35x+16x−10x2=5
-35x+16x=5
-19x=5
=>x=-5/19