ko thay doi

Không 

Tui lớp 2

96 tháng =)

x+12=3

=> x=3-12

=> x=-9

x+43=67

=> x=67-43

=> x=24

x+23=67

=> x=67-23

=> x=44

Bạn viết sai đè rồi

Sắp xếp theo thứ tự từ bé đến lớn là : \(\frac{9}{26};\frac{4}{5};\frac{12}{5};\frac{34}{7};\frac{67}{12}\)

a) (100 + 67) x 67 + (200 - 33) x 33

= 167 x 67 + 167 x 33

= 167 x (67 + 33)

= 167 x 100

= 16700

b) 45,651 x 73 + 45,651 x 20 + 45,651 x 7

= 45,651 x (73 + 20 + 7)

= 45,651 x 100

= 4565,1

c) 14,2 x 30 + 14,2 x 57 + 14,2 x 13

= 14,2 x (30 + 57 + 13)

= 14,2 x 100

= 1420

a) (100 + 67) × 67 + (200 - 33) × 33

= 167 × 67 + 167 × 33

= 167 × 100

= 16700

b) 45,651 × 73 + 45,651 × 20 + 45,651 × 7

= 45,651 × (73 + 20 + 7)

= 45,651 × 100

= 4565,1

c) 14,2 × 30 + 14,2 × 57 + 14,2 × 13

= 14,2 × (30 + 57 + 13)

= 14,2 × 100

= 1420

\(a,5^{x-2}=125\)

\(\Rightarrow5^{x-2}=5^3\)

\(\Rightarrow x-2=3\)

\(\Rightarrow x=5\)

\(b,3^{x+4}=243\)

\(\Rightarrow3^{x+4}=3^5\)

\(\Rightarrow x+4=5\)

\(\Rightarrow x=1\)

\(5^{x-2}=125\)

\(\Rightarrow5^{x-2}=5^3\)

\(\Rightarrow x-2=3\)

\(\Rightarrow x=3+2\)

\(\Rightarrow x=5\)

bai tap nay lop may day

Điên à 

\(\left(\dfrac{1}{3}+\dfrac{12}{67}+\dfrac{13}{41}\right)-\left(\dfrac{79}{67}-\dfrac{28}{41}\right)\\ =\left(\dfrac{103}{201}+\dfrac{13}{41}\right)-\dfrac{1363}{2747}\\ =\dfrac{6836}{8241}-\dfrac{1363}{2747}\\ =\dfrac{1}{3}\)

\(\left(\dfrac{1}{3}+\dfrac{12}{67}+\dfrac{13}{41}\right)-\left(\dfrac{79}{67}-\dfrac{28}{41}\right)\\ =\dfrac{1}{3}+\dfrac{12}{67}+\dfrac{13}{41}-\dfrac{79}{67}+\dfrac{28}{41}\\ =\dfrac{1}{3}+\left(\dfrac{12}{67}-\dfrac{79}{67}\right)+\left(\dfrac{13}{41}+\dfrac{28}{41}\right)\\ =\dfrac{1}{3}-\dfrac{67}{67}+\dfrac{41}{41}\\ =\dfrac{1}{3}-1+1\\ =\dfrac{1}{3}\)