42/x=90/105???????????????????
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(x-\dfrac{5}{15}=\dfrac{42}{105}\)
\(\Rightarrow x=\dfrac{42}{105}+\dfrac{5}{15}\)
\(\Rightarrow x=\dfrac{11}{15}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
42 - x = 105 : 15 + 18
42 - x = 7 + 18 = 25
x = 42 - 25 = 17
( x - 22 x 10 ) : 11 = 39
x - 220 = 39 x 11 = 429
x = 429 + 220 = 649
42 - x = 7 + 18
<=> 42 - x = 25
<=> x= 17
( x - 220) : 11 = 39
x - 220 = 429
x = 209
![](https://rs.olm.vn/images/avt/0.png?1311)
\(\frac{x}{5}=\frac{42}{105}\Rightarrow x.105=5.42\Rightarrow x=\frac{5.42}{105}=2\)
\(\frac{y}{10}=\frac{42}{105}\Rightarrow y.105=10.42\Rightarrow y=\frac{10.42}{105}=4\)
\(\frac{z}{-80}=\frac{42}{105}\Rightarrow z.105=-80.42\Rightarrow z=-\frac{80.42}{105}=-32\)
Vậy x = 2; y = 4; z = -32.
\(\frac{x}{5}=\frac{42}{105}\Rightarrow105.x=42.5\Rightarrow x=2\)
\(\frac{2}{5}=\frac{y}{10}\Rightarrow5.y=2.10\Rightarrow y=4\)
\(\frac{4}{10}=\frac{z}{-80}\Rightarrow10.z=4.-80\Rightarrow z=-32\)
Vậy x=2;y=4 và z=-32
![](https://rs.olm.vn/images/avt/0.png?1311)
a) \(\left(45x105-225\right)-\left(210+42x95\right)\)
\(=45x\left(100+5\right)-225-210+42x\left(100-5\right)\)
\(=4500+45x5-225-210+4200-42x5\)
\(=4500+4200+45x5-42x5-225-210\)
\(=8700+5x\left(45-42\right)-435\)
\(=8700+15-435=8280\)
a: =45*105-225-210-42*95
=45*(105-5)-42(95+5)
=100*3
=300
b: =47(105-5)-42(96+4)
=47*100-42*100
=5*100
=500
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
ủng hộ mình lên 200 bạn nha
42/49
ung ho len 130 nha