X: 0.1 + X : 0.5 - X : 25% + X + X = 2019
x+0.1+x+0.2+x..........+x+0.5=5.55
X+ 0,1+X+0,2+...+X+0,5=5,55
<=> 5x X + (0,5+0,1) x 5 :2 = 5,55
<=> 5 x X + 1,5 = 5,55
<=> 5 x X= 5,55- 1,5
<=> 5 x X= 4,05
<=>X= 4,05:5
<=>X=0,81
Ta có: x+0,1+x+0,2+x+...+x+0,5=5,55
nên 5x+1,5=5,55
\(\Leftrightarrow5x=4,05\)
hay x=0,81
Vậy: x=0,81
x/0.5+x/0.25+x/0.1=16
tính giá trị biểu thức ( 11 x 9 - 900 x 0.1- 8) x ( 56.7 x 0.5 + 56.7 x 9.5)
( 11 x 9 - 900 x 0.1- 8) x ( 56.7 x 0.5 + 56.7 x 9.5)
=(99 - 90 - 8) x [56.7(0.5+9.5)]
=1 x [56.7x10]
=1x 567=567
( 11 x 9 - 900 x 0.1- 8) x ( 56.7 x 0.5 + 56.7 x 9.5)
=(99 - 90 - 8) x [56.7(0.5+9.5)]
=1 x [56.7x10]
=1x 567=567
tinh bang cach thuan tien
a. 7.15 : 0.5 + 7.15 x 9 - 7.15
b. 3.14 : 0.1 + 75 % x 3.14 + 3.14 : 0.125 + 81.25 x 3.14
\(a.7,15:0,5+7,15.9-7,15=7,15.\left(2+1-1\right)\)
\(=7,15.10=71,5.\)
\(b.3,14:0,1+75\%.3,14+3,14:0,125+81,25.3,14=3,14.\left(10+\frac{3}{4}+8+81,25\right)\)
\(=3,14.100=314.\)
7.15*2+7.15*9-7.15
7.15*(2+9-1)
7.15*10
71.5
b, 3.14*10+7.5*3.14+3.14*8+81.25*3.14
=314*(10+7.5+8+81.25)
=3.14*106.75
=355.195
x/10^2019+(0.1)^2019=(1 phần 10)^2019
giải giúp mik nha
\(\frac{x}{10}\)^2019+(0,1)^2019=\(\frac{1}{10}\)^2019 \(\frac{x}{10}\)^2019 =(0,1)^2019-(0,1)^2019 \(\frac{x}{10}\)^2019 =0 \(\frac{x}{10}\)^2019 =0^2019 \(\frac{x}{10}\) =0 x =0
a) 2019/2020 x 4/11 + 2019/2020 x 5/11 + 2019/2020 x 2/11
b) 17/14 x 25/27 - 1/14 x 25/27 - 2/14 x 25/27
\(a.=\dfrac{2019}{2020}\times\left(\dfrac{4}{11}+\dfrac{5}{11}+\dfrac{2}{11}\right)\\ =\dfrac{2019}{2020}\times1=\dfrac{2019}{2020}\\ b.=\dfrac{25}{27}\times\left(\dfrac{17}{14}-\dfrac{1}{14}-\dfrac{2}{14}\right)\\ =\dfrac{25}{27}\times1=\dfrac{25}{27}\)
Bài 1:
a) Tìm x: 75%* x+3/4*x +x=30
b)tính giá trị bieu thức: 1/2:0.5-1/4:0.25+1/8:0.125-1/10:0.1
TA CÓ 25-Y^2=8(X-2019)^2
SUY RA 8(X-2019)^2 LỚN HƠN HOẶC BẰNG 25
SUY RA (X-2019)^2 LỚN HƠN HOẶC BẰNG 25 PHẦN 8
MÀ (X-2019)^2 LÀ SỐ CHÍNH PHƯƠNG
SUY RA (X-2019)^2 =0 HOẶC 1
NẾU (X-2019)^2 =0
SUY RA X-2019=0
SUY RA X=2019
SUY RA 25 -Y^2=0
SUY RA Y^2=25
SUY RA Y=5
NẾU (X-2019)^2 =1
SUY RA X-2019=1
SUY RA X=2020
HOẶC X-2019=-1
SUY RA X= 2018
thiếu 1 số chỗ đó
cứ thấy sai sai chỗ nào ý
2019 x 74+ 2019 x 25 + 2019
2019 x 74+ 2019 x 25 + 2019
2019 x 74 + 2019 x 25 + 2019 x 1
2019 x (74 + 25 + 1)
2019 x 100
= 201900