\(5.\left(13-26\right)-26.\left(13-5\right)+21.13\)
\(=65-130-338+130+273\)
\(=0\)
5.(13-26)-26.(13-5)+21.13
= 5.(-13)-26.8+273
= (-65)-208+273
= (-273)+273
= 0
đúng thì **** nha
63x(64-62)+62x(62-64)
5x(13-26)-26x(13-5)+21x13
bài 1
a) 26+5x=3x-56
b)13/4x-7/6x=-5/12+5/3
c)x/ (-5/14)+7/2=-1 và 2/3
Câu 1 (4.5 điểm):
Tìm số nguyên x,biết:
a/x+13=26x+13=26 b/x−14=1−2x−14=1−2 c/−16=32x−16=32x d/45=−129−x45=−129−x e/x+13=3x+1x+13=3x+1 f/x−1−4=−4x−1
c) \(\dfrac{8}{15}\).\(\dfrac{5}{13}\)+\(\dfrac{5}{13}\).\(\dfrac{26}{15}\).\(\dfrac{5}{13}\).\(\dfrac{8}{15}\)
4. Tính hợp lí :
\(\dfrac{5}{13}\) . \(\dfrac{8}{15}\) + \(\dfrac{5}{13}\) . \(\dfrac{26}{15}\) - \(\dfrac{5}{13}\) . \(\dfrac{8}{15}\)
Bài 3
Câu 2) 72 : (x – 15) = 8
Câu 3) 3/ 90 – 3x = 3
Câu 4) 9x - 26= 109
Câu 5) -5x + 13= 23
Câu 6) 3x - 28= -22
Câu 7) 2x : ( -3) = 6
Câu 8) 108 : ( 5 - x ) = -3
Mấy bạn ghi cách viết ra luôn cho mình với
4.24.5^2-(3^3.18+3^3.12)
31.15.7^2.4-31.49.40
1+2+3+4+5+6+7+8+9+10
1+3+5+7+9+11+13+15+19
2+6+10+14+22+23+26+34
5+8+11+14+17+20+23+26+29
1+6+11+16+21+26+31+36+41+47+51
10+13+16+19+22+25+28+31+34+37+40
5+7+9+11+13+15+17+3+8+13+18+23+28
4+7+10+13+16+19+5+9+13+17+21+25
26% của 50 bằng
A.26 B.13 C.10 D.5
tính nhanh :
a) 5/13 . (6/29 - 26/39) - 6/29 . (5/13 - 29/6)
b)1.198 + 2.197 + 3.196 +...+ 198.1 / 1.2 + 2.3 + 3.4 +...+ 198.199
