1. Let x be the original amount of baseball cards,
2. half of x was lost so x divided by 2.
3. you buy 18 cards to replace some that were lost
4. You can find the awnser by subtracting 18 from 30, which is 12.
5. Now lets remember that half of your cards were lost. meaning that 12 is only half of what you started with.
6. 12 times 2 would be 24.
7. The Awnser is 24
8. To check your work, you can say x=24, 24 divided by 2 is 12, and 12 plus 18 is 30.
Answer: Thats technically a rhombus, but since thats not an option its a parallelogram
Step-by-step explanation:
Answer Is C.
Answer:
The distance between the astronomers and the moon was ![7.56*10^{8]](https://tex.z-dn.net/?f=7.56%2A10%5E%7B8%5D)
meters.
Step-by-step explanation:
We have that the speed is the distance divided by the time, so:
In this problem, we have that:
The reflected laser beam was observed by the astronomers 2.52 s after the laser pulse was sent. This means that 
.
If the speed of light is 3.00 times 10^8 m/s, what was the distance between the astronomers and the moon?
We have that 
m/s.
We have to find d. So:
The distance between the astronomers and the moon was meters.
Answer:
x = -3
Step-by-step explanation:
y = -x + 2
7x + 4y = -1
Subsitution method: (Substitute y)
7x + 4(-x+2) = -1
Expand.
7x + (-4x + 8) = -1
One plus and one minus make one minus. Two plus makes a plus.
7x -4x + 8 = -1
Simplify.
3x + 8 = -1
Isolate 3x.
3x = -1-8
= -9
Find x.
x = -9 ÷ 3
= -3
