Answer:
x=5/2 + a/2, y= 5/2 - a/2
Step-by-step explanation:
We can solve this system using addition of the equations
x+y=5
<u>x-y=a</u>
2x =(5+a)
x=(5+a)/2= 5/2 +a/2
x=5/2 +a/2
x-y=a
y = x - a , x=5/2 + a/2
y= 5/2 + a/2-a
y= 5/2 - a/2
It’s C that’s the only one that works
They are asking which one gives both the same answer.
Solving this problem is just pretty straight forward. All
we have to do is to use the concept of ratio and proportion.
First, let us say that the change in elevation in half an
hour (30 minutes) takes the value of variable x.
From the given, we know that the ratio of height and time
is:
152 m : 8 minutes
And the next ratio is:
x : 30 minutes
To solve for the value of x, we equate the two:
152 m : 8 minutes = x : 30 minutes
We know that the symbol of ratio which is “:” also means
division, therefore:
152 m / 8 minutes = x / 30 minutes
x = 152 m * 30 minutes / 8 minutes
x = 570 m
Therefore the change in elevation after half an hour is
570 meters.
