làm 2 cách
1/4 x 5/12 x 5/12 x 4/5
Điền Đ(đúng) hoặc S(sai) vào chỗ chẫm :
A) 5/6 + ( 7/12 x 1/4) = 5/6 x 7/12 + 5/6 x1/4 .....
b) 2/3 x ( 4/5 + 2/3 ) = 2/3 x 4/5 + 2/3 x 2/3 ........
Làm gấp giúp mình nha !
a) sai
b) đúng
a) Đúng
b) Đúng
1) Tính
a) 9/12 - 5/12 ; 9/12 - 1/3 ; 7 - 3/2 ; 9/4 - 2
b) 2/7 + 5/7 ; 1/3 + 5/12 ; 2 + 2/5 ; 6/9 + 3
c) 2/3 x 4/7 ; 3/11 x 2 ; 4 x 2/7
d) 8/21 : 4/7 ; 8/7 : 4 ; 5 : 2/3
AI LÀM NHANH VÀ ĐÚNG NHẤT THÌ MÌNH TICK CHO!!!!
a] 4/12 ; 5/12 ; 11/2 ; 1/4
b] 1 ; 9/12; 12/5 ; 11/3
c] 8/21; 6/11;8/7
d] 2/3 ;2/7 15/2
a]1/3 5/12 11/2 1/4
b]1 3/4 12/5 33/9
c]8/21 6/11 8/7
d]2/3 2/7 15/2
a) 1/3 ; 5/12 ; 11/2 ; 1/14
b) 1 ; 9/12 ; 12/5 ; 11/3
c) 8/21 ; 6/11 ; 8/7
d) 2/3 ; 2/7 ; 15/2
Tính nhẩm:
3 x 4 = 12 2 x 5 = 5 x 3 = 4 x 2 =
12 : 3 = 10 : 2 = 15 : 3 = 8 : 2 =
12 : 4 = 10 : 5 = 15 : 5 = 8 : 4 =
Ta tính nhẩm như sau:
3x4=12 2x5=10 5x3=15 4x2=8
12:3=4 10:2=5 15:3=5 8:2=4
12:4=3 10:5=2 15:5=3 8:4=2
3x4 = 12 2x5 = 10 5x3 = 15 4x2 =8
12 : 3 = 4 10 : 2 = 5 15 : 3 = 5 8 : 2 = 4
12 : 4 =3 10 :5 = 2 15 : 5 = 3 8 : 4 = 2
Ai làm nhanh sẽ được tick, mau mau:
1) 10 x 2 : 3 x 9 : 5 = ...?
2) 12 x 6 x 7 : 2 : 9 = ...?
3) 12 x 5 x 6 : 2 : 1 = ...?
4) 50 x 5 : 10 : 2 x 4 = ...?
5) 100 x 6 : 3 : 2 : 5 = ...?
câu 1: (x-2)(x2+2x+4)+25x=x(x+5)(x-5)+8
câu 2: \(\dfrac{x+5}{4}\)+\(\dfrac{3+2x}{3}\)=\(\dfrac{6x-1}{3}\)-\(\dfrac{1-2x}{12}\)
câu 3:\(\dfrac{x-4}{3}\)-\(\dfrac{3x-1}{12}\)=\(\dfrac{3x+1}{4}\)+\(\dfrac{9x-2}{8}\)
Giúp mình với ai làm mà có lời giải rõ á là mình tym nha làm ơn
Câu 1:
\(\left(x-2\right)\left(x^2+2x+4\right)+25x=x\left(x+5\right)\left(x-5\right)+8\)
\(\Leftrightarrow x^3-8+25x=x\left(x^2-25\right)+8\)
\(\Leftrightarrow x^3-8+25x=x^3-25x+8\)
\(\Leftrightarrow x^3-8+25x-x^3+25x-8=0\)
\(\Leftrightarrow50x-16=0\)
\(\Leftrightarrow50x=16\)
\(\Leftrightarrow x=\dfrac{8}{25}\)
Câu 2 :
\(\dfrac{x+5}{4}+\dfrac{3+2x}{3}=\dfrac{6x-1}{3}-\dfrac{1-2x}{12}\)
<=> \(\dfrac{3\left(x+5\right)}{12}+\dfrac{4\left(3+2x\right)}{12}=\dfrac{4\left(6x-1\right)}{12}-\dfrac{1-2x}{12}\)
<=>\(\dfrac{3x+15+12+8x}{12}=\dfrac{24x-4-1+2x}{12}\)
<=> 3x + 15 + 12 + 8x = 24x - 4 - 1 +2x
<=> 11x+27 = 26x -5
<=> ( 26x - 5 ) - ( 11x + 27 ) = 0
<=> 15x - 32 = 0
<=> 15x = 32
<=> x = \(\dfrac{32}{15}\)
Câu 3:
x - 4/3 - 3x - 1/12 = 3x + 1/4 + 9x - 2/8
<=> 4x - 16 - 3x + 1/12 = 6x + 2 + 9x - 2/8
<=> x - 15/12 = 15x/8
<=> 8x - 120 = 180x
<=> 120 = -172x <=> x = -172/120 = -43/30
ĐẠI SỐ 7
Rút gọn : A = 4^6 x 9^5 + 6^9 x 120 / 6^11 - 8^4 x 3^12
B = 2^12 x 3^5 - 4^6 x 9^2 / ( 2^2 x 3 )^6 + 8^4 x 3^5
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Ai làm dc thì giúp mình nheee )) Camon :))
Tìm số nguyên x, biết:
1/ 2(x- 5) -3(x +7)=14
2/ 5(x-6)-2(x +3)= 12
3/ -7(5-x)-2(x-10)= 15
4/ 3 ( x-4)-(8- x) = 12
5/ 4(x-5)-3(x+7)= -19
6/ 7(x-3)-5(3-x)=11x -5
7/ 4(2-x)+3(x-5)=14
Ai làm đúng mình tick 2 cái
1) 2(x - 5) - 3(x + 7) = 14
2x - 10 - 3x - 21 = 14
2x - 3x = 14 + 21 + 10
- x = 45
x = -45
2) 5(x - 6) - 2(x + 3) = 12
5x - 30 - 2x - 6 = 12
3x = 12+ 30 + 6
3x = 48
x = 16
3) -7(5 - x) - 2(x - 10) = 15
-35 + 7x - 2x + 20 = 15
5x = 15 - 20 + 35
5x = 30
x = 6
4) 3(x - 4) - (8 - x) = 12
3x - 12 - 8 + x =12
4x = 12 + 8 + 12
4x = 32
x = 8
5) 4(x - 5) - 3(x + 7) = -19
4x - 20 - 3x - 21 = -19
x = -19 + 21 + 20
x = 22
6) 7(x - 3) - 5(3 - x) = 11x - 5
7x - 21 - 15 + 5x = 11x - 5
7x + 5x - 11x = -5 + 21 + 15
x = 31
7) 4(2 - x) + 3(x - 5) = 14
8 - 4x + 3x - 15 = 14
- x = 14 + 15 - 8
- x = 21
x = -21
720 : ( x . 2 + x . 3 ) = 3.2
720 : ( x . 2 + x.3 ) = 6
( x .2 + x.3 ) = 720 : 6
x.2+x.3 = 120
x . ( 2 + 3 ) = 120
x . 5 = 120
x = 120 : 5
x = 24
2tìm x
-11/12x+3/4=1/63-(1/6-x).2/3=23x/3=12/xlàm ơn giúp mình đi\(1,\)
\(A=-\frac{7}{12}+\frac{12}{18}+\frac{5}{4}\)
\(=-\frac{7}{12}+\frac{2}{3}+\frac{5}{4}\)
\(=-\frac{7}{12}+\frac{8}{12}+\frac{15}{12}\)
\(=\frac{-7+8+15}{12}\)
\(=\frac{4}{3}\)
\(1,\)
\(B=\frac{1}{4}-\frac{8}{7}:8-3:\frac{3}{4}.\left(-2\right)^2\)
\(=\frac{1}{4}-\frac{8}{7}.\frac{1}{8}-3.\frac{4}{3}.4\)
\(=\frac{1}{4}-\frac{1}{7}-16\)
\(=\frac{7-4-448}{28}\)
\(=-\frac{445}{28}\)
Mình đang bận, bạn cần gấp thế à? Trả lời trong tin nhắn nhé!!!
2.B=1/4-(8/7:8)-(3:3/8).(-2)^2=1/4-(8/7.1/8)-(3/1.4/3).(-2)^2=1/4-1/7-4.(-2)^2=1/4-1/7-16= 7/28-4/28-448/28= -445/28
Tìm x: a , 7 3/5 : x = 5 4/15 - 1 1/6 b, x × 2 2/3 = 3 4/8 + 6 5/12 có ai bik làm ko bik làm thì chỉ mình với ai đúng thì tớ like
a, 7\(\dfrac{3}{5}\) : \(x\) = 5\(\dfrac{4}{15}\) - 1\(\dfrac{1}{6}\)
\(\dfrac{38}{5}\) : \(x\) = \(\dfrac{79}{15}\) - \(\dfrac{7}{6}\)
\(x\) = \(\dfrac{41}{10}\)
\(x\) = \(\dfrac{38}{5}\) : \(\dfrac{41}{10}\)
\(x\) = \(\dfrac{76}{41}\)
b, \(x\) \(\times\) 2\(\dfrac{2}{3}\) = 3\(\dfrac{4}{8}\) + 6\(\dfrac{5}{12}\)
\(x\) \(\times\) \(\dfrac{8}{3}\) = \(\dfrac{7}{2}\) + \(\dfrac{77}{12}\)
\(x\) \(\times\) \(\dfrac{8}{3}\) = \(\dfrac{119}{12}\)
\(x\) = \(\dfrac{119}{12}\)
\(x\) = \(\dfrac{119}{12}\): \(\dfrac{8}{3}\)
\(x\) = \(\dfrac{119}{32}\)