The answer is 72 hope that helped love :)<3
Answer:
Distance between A and B is 5400 meters
Step-by-step explanation:
Consider "D" the letter to identify distance between A and B
Let's use "t" to identify the time of the first encounter (Devi and Kumar), and create an equation that states that the distance covered by Devi (at 100 m/min) in time "t", is equal to the total distance D minus what Kumar has covered at his speed (80 m/min) in that same time:
Recall that distance equals the speed times the time:
distance= speed * time
First encounter:
100 * t = D - 80 * t
180 * t = D Equation (1)
Not, 6 minutes later (at time t+6) , Devi and Li Ting meet .
Then for this encounter the distance covered by Devi equals total distance d minus the distance covered by Li Ting:
100 *(t+6) = D - 75 * (t+6)
100 t + 600 = D - 75 t - 450
175 T + 150 = D Equation (2)
Now, let's equal equation (1) to equation (2), since D should be the same:
180 t = 175 t + 150
5 t = 150
t = 30
Then the time t (first encounter) is 30 minutes. Knowing this, we can use either equation to find D:
From Equation (1) for example: D = 180 * t = 180 * 30 = 5400 meters
Answer:

Step-by-step explanation:
we know that
The area of the figure is equal to the area of rectangle plus the area of two semicircles
<u>The area of rectangle is equal to</u>

<u>The area of the small semicircle is equal to</u>

-----> radius is half the diameter
substitute

<u>The area of the larger semicircle is equal to</u>

-----> radius is half the diameter
substitute

The area of the figure is equal to

-2.7639320225 is the exact when estimated -3 hope this helped if can pls mark as brainliest have a great day!
Answer:
37. {-1, -1}.
Step-by-step explanation:
I'll solve the first one . The other can be solved in a similar way. We can use the method of elimination.
x1 - x2 = 0
3x1 - 2x2 = -1
We can multiply the first equation by -2. We then have an equation containing + 2x2 so when we add this to the second equation the 2x2 will be eliminated
So the first equation becomes:
-2x1 + 2x2 = 0 Bring down the second equation:
3x1 - 2x2 = -1 Now adding, we get:
x1 + 0 = -1
so x1 = -1.
Now we substitute this value of x1 in the original first equation:
-1 - x2 = 0
-1 = x2
x2 = -1.
So the solution set is {-1, -1}.
If there are more than 2 equations you can use a combination of substitutions and eliminations.