a) (y + 5) x 2020 = 205 x 2020

(y + 5) x 2020 = 414100

y + 5 = 414100 : 2020 = 205

y = 205 - 5 = 200

a) y= 200

b) y-45600 = 1600 × 4 ×25

y-45600=160000

y= 114400

b) y - 45600 = (2019 - 419) x 4 x 25

y - 45600 = 1600 x 100

y - 45600 = 160000

y = 160000 + 45600 = 205 600

Bài 1: Tìm y.

\(a)\dfrac{19}{20}-y=\dfrac{8}{5}-\dfrac{3}{4}\\ \dfrac{19}{20}-y=\dfrac{17}{20}\\ y=\dfrac{19}{20}-\dfrac{17}{20}\\ y=\dfrac{2}{20}\\ y=\dfrac{1}{10}\\ b)y:\dfrac{2}{3}=\dfrac{4}{9}\times3\\ y:\dfrac{2}{3}=\dfrac{4}{3}\\ y=\dfrac{4}{3}\times\dfrac{2}{3}\\ y=\dfrac{8}{9}\) 

Bài 2:                                      Giải:

Chiều cao của mảnh vườn đó là:

\(\dfrac{2}{3}-\dfrac{1}{4}=\dfrac{5}{12}\left(km\right)\) 

Diện tích mảnh vườn đó là:

\(\dfrac{2}{3}\times\dfrac{5}{12}=\dfrac{5}{18}\left(km^2\right)\) 

Đáp số: \(\dfrac{5}{18}km^2.\)

Bài 1

a) 19/20 - y = 8/5 - 3/4

19/20 - y = 32/20 - 15/20

19/20 - y = 17/20

y = 19/20 - 17/20

y = 2/20 = 1/10

b) y : 2/3 = 4/9 × 3

y : 2/3 = 4/3

y = 4/3 × 2/3

y = 8/3

--------------------

Bài 2

Chiều cao mảnh vườn:

2/3 - 1/4 = 5/12 (km)

Diện tích mảnh vườn:

2/3 × 5/12 = 5/18 (km²)

Bài 1: 

a) \(\dfrac{19}{20}-y=\dfrac{8}{5}-\dfrac{3}{4}\)

\(\dfrac{19}{20}-y=\dfrac{17}{20}\)

\(y=\dfrac{19}{20}-\dfrac{17}{20}\)

\(y=\dfrac{2}{20}=\dfrac{1}{10}\)

b) \(y:\dfrac{2}{3}=\dfrac{4}{9}\times3\)

\(y:\dfrac{2}{3}=\dfrac{4}{3}\)

\(y=\dfrac{4}{3}\times\dfrac{2}{3}\)

\(y=\dfrac{8}{9}\)

Bài 2: 

Giải:

Chiều cao của hình bình hành: \(\dfrac{2}{3}\times\dfrac{1}{4}=\dfrac{1}{6}\left(km\right)\)

Diện tích mảnh vườn: \(\dfrac{1}{6}\times\dfrac{2}{3}=\dfrac{1}{9}\left(km^2\right)\)

Đáp số: \(\dfrac{1}{9}km^2\)

a: =>y=1,25x3,14=3,925

b: =>y:0,24=15-7,8=7,2

hay y=1,728

c: =>10y=36,7

hay y=3,67

d: =>6:y=1,5

hay y=4

e: =>4y+0,2y=44,1

=>4,2y=44,1

hay y=10,5

a: Ta có: \(x^2\ge0\forall x\)

\(\left(y-\dfrac{1}{10}\right)^4\ge0\forall y\)

Do đó: \(x^2+\left(y-\dfrac{1}{10}\right)^4\ge0\forall x,y\)

Dấu '=' xảy ra khi \(\left(x,y\right)=\left(0;\dfrac{1}{10}\right)\)

a)\(162:y+216:y=6\)

⇔\(\left(162+216\right):y=6\)

⇔\(378:y=6\)

⇔\(y=63\)

b)\(602:y+123.2=253\)

⇔\(602:y+246=253\)

⇔\(602:y=7\)

⇔\(y=86\)

c)\(8\left(15720-y\right)=51784\)

⇔\(125760-8y=51784\)

⇔\(8y=73976\)

⇔\(y=9247\)

Tìm y:

\(a,y+847\times2=1953-74\\ y+847\times2=1879\\ y+1694=1897\\ y=1897-1694\\ y=185\\ b,y:\left(7\times18\right)=5839+8591\\ y:126=14430\\ y=14430\times126\\ y=1818180.\)

a/ y + 847 x 2 = 1953 - 74
y + 1694 = 1879
y = 1879 - 1694
y = 185
b/y : (7 x 18) = 5839 + 8591
y : 126 = 14430
y = 14430 x 126
y = 1818180
#AvoidMe

 a. y + 847 x 2 = 1953 - 74

y + 1694 = 1879                              

            y = 1879 - 1694

            y = 185

 b. y : (7 x 18) = 5839 + 8591

y : 126 = 14430

              y = 14430 x 126

              y = 1818180

\(a,y\times2,8+5,2\times y=48\\ y\times\left(2,8+5,2\right)=48\\ y\times8=48\\ y=\dfrac{48}{8}=6\\ ---\\ b,y\times12,25-y+y\times2,75=1050\\ y\times\left(12,25-1+2,75\right)=1050\\ y\times14=1050\\ y=\dfrac{1050}{14}=75\)

a: \(y\cdot2,8+y\cdot5,2=48\)

=>\(y\left(2,8+5,2\right)=48\)

=>\(8y=48\)

=>\(y=\dfrac{48}{8}=6\)

b: \(y\cdot12,25-y+y\cdot2,75=1050\)

=>\(y\left(12,25-1+2,75\right)=1050\)

=>\(y\cdot14=1050\)

=>\(y=\dfrac{1050}{14}=75\)

\(a,y\times27+y\times30+y\times44-y=10500\\\Rightarrow y\times\left(27+30+44-1\right)=10500\\ \Rightarrow y\times100=10500\\ \Rightarrow y=10500:100\\ \Rightarrow y=105\\ b,y\times285+115\times y=400\\ \Rightarrow y\times\left(285+115\right)=40\\ \Rightarrow y\times400=400\\ y=400:400\\ \Rightarrow y=1\)

\(a,\Rightarrow y\times\left(27+30+44-1\right)=10500\\ \Rightarrow y\times100=10500\\ \Rightarrow y=105\\ b,\Rightarrow y\times\left(285+115\right)=400\\ \Rightarrow y\times400=400\\ \Rightarrow y=1\)

a: =>y=0,056:7=0,008

b: =>y=21/50:6=21/300=0,07

a, 0,008

b, 0,07