Answer:
Step-by-step explanation:
hola
Cuando dos numeros tienen el mismo signo la respuesta siempre es positiva. cuando un signo es positivo y e lotro es negativo la respuesta siempre sera negativa. Esta es la regla para multiplicar numeros con signos diferentes. el orden de los signos no importa en multiplicacon siempre va ha ser la misma respuesta.
Answer:
Area = 10
Step-by-step explanation:
(
×
) ÷ 2 = 10
Answer:
-1266
Step-by-step explanation:
![(28 \times 5 - 5 \times 190) - 2 \times 228 \\ (140 - 950) - 456 \\ ( - 810) - 456 \\ - 810 - 456](https://tex.z-dn.net/?f=%2828%20%5Ctimes%205%20-%205%20%5Ctimes%20190%29%20-%202%20%5Ctimes%20228%20%5C%5C%20%28140%20-%20950%29%20-%20456%20%5C%5C%20%28%20-%20810%29%20-%20456%20%5C%5C%20%20-%20810%20-%20456)
![= - 1266](https://tex.z-dn.net/?f=%20%3D%20%20-%201266)
473,000 u round up to the next thousand
Answer:
20 mph
Step-by-step explanation:
Let speed of Train a = Va mph
Let speed of Train b = Vb mph
Va = Vb + 30
Let time taken for Train a = Ta
Let time taken for Train b = Tb
time taken = distance travelled/speed
Ta = 350/Va = 350/(Vb+30)
Tb = 140/Vb
But they both travel in the same amount of time.
So, Ta = Tb
![\frac{350}{v_{b} + 30}=\frac{140}{v_{b}}](https://tex.z-dn.net/?f=%5Cfrac%7B350%7D%7Bv_%7Bb%7D%20%2B%2030%7D%3D%5Cfrac%7B140%7D%7Bv_%7Bb%7D%7D)
Cross multiply
![350v_{b} = 140(v_{b} + 30)\\\\350v_{b} = 140v_{b} + 4200\\\\350v_{b} -140v_{b} = 4200\\\\210v_{b} = 4200](https://tex.z-dn.net/?f=350v_%7Bb%7D%20%3D%20140%28v_%7Bb%7D%20%2B%2030%29%5C%5C%5C%5C350v_%7Bb%7D%20%3D%20140v_%7Bb%7D%20%2B%204200%5C%5C%5C%5C350v_%7Bb%7D%20-140v_%7Bb%7D%20%3D%204200%5C%5C%5C%5C210v_%7Bb%7D%20%3D%204200)
Divide both sides by 210
![\frac{210v_{b} }{210} \frac{4200}{210} \\\\v_{b} = 20 mph](https://tex.z-dn.net/?f=%5Cfrac%7B210v_%7Bb%7D%20%7D%7B210%7D%20%5Cfrac%7B4200%7D%7B210%7D%20%5C%5C%5C%5Cv_%7Bb%7D%20%3D%2020%20mph)