Answer:
All of them could be correct, since there aren't any dimentions provided.
Step-by-step explanation:
<u>Answer</u>
Incorrect
<u>Explanation</u>
Unpack the problem:
Let the distance round the track to be X.
Speed is the ratio of distance to time.
Robert run a distance of (1/2)x
Elaine run a distance of (3/4)x
Make a plan:
Finding the speed of each.
Compare their speeds to determine who ran faster than who.
Solution:
Robert's speed =(1/2)x/(5/6)
=1/2×6/5x
= (3/5)x
= 0.6x
Elaine's speed = (3/4)x/(9/10)
= (3/4)×(10/9)x
= (5/6)x
= 0.83333x
<em>Elaine ran faster than Robert. </em>
<u>Look back and explain:</u>
0.83333x > 0.6x
Elaine's speed is higher than Robert's speed.
This shows that Elaine ran faster than Robert.
If they are parallel they will have the same slope , m
So in y = mx + c, if there are two equations which both have the same m value they will be parallel.
If the lines are perpendicular they'll have slopes like this: 1/2 to -2/1 - where they flip and a negative gets added.
In the equations: 10x + 5y = -5 , and y = -2x + 6
We can rearrange 10x + 5y = -5 to be in the form y = mx + c
10x + 5y = -5
5y = -5 - 10x
y = -1 - 2x
y = -2x - 1
Since y = -2x - 1 and y = -2x + 6 both have the same slope of -2 they are parallel!
Usando las relaciones entre velocidad, distancia y tiempo, se encuentra que ella condujo a una velocidad media de 90,5 km/h.
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La <u>velocidad </u><u>es la distancia dividida por el tiempo</u>, por lo que:

- Total de 135,75 km, o sea,

- Llego en 1,5 horas, o sea,

La velocidad es:

División de decimales, o sea, seguimos multiplicando los números por 10 hasta que ninguno sea decimal:

Ella condujo a una velocidad media de 90,5 km/h.
Un problema similar es dado en brainly.com/question/24558377
Answer:
Step-by-step explanation: since average speed = total distance/time
a)average speed of the journey from my home town to A = 10 miles/20 minutes = 0.5
b)journey from my home town to B = 20 miles/30 minutes = 0.7
c)10 miles + 20 miles = 30 miles
which takes 50 minutes
so: 30 miles/50 minutes = 0.6