I:2x – y + z = 7
II:x + 2y – 5z = -1
III:x – y = 6
you can first use III and substitute x or y to eliminate it in I and II (in this case x):
III: x=6+y
-> substitute x in I and II:
I': 2*(6+y)-y+z=7
12+2y-y+z=7
y+z=-5
II':(6+y)+2y-5z=-1
3y+6-5z=-1
3y-5z=-7
then you can subtract II' from 3*I' to eliminate y:
3*I'=3y+3z=-15
3*I'-II':
3y+3z-(3y-5z)=-15-(-7)
8z=-8
z=-1
insert z in II' to calculate y:
3y-5z=-7
3y+5=-7
3y=-12
y=-4
insert y into III to calculate x:
x-(-4)=6
x+4=6
x=2
so the solution is
x=2
y=-4
z=-1
8/10
4x2=8
5x2=10
this is how you know they are equal
A polygon has the following coordinates: A(3,-3), B(-3,-2), C(-5,1), D(-5,4), E(-4,6), F(-2,6), G(3,2). Find the length of CD.
slavikrds [6]
Answer:
3
Step-by-step explanation:
C (-5,1)
D (-5,4)
C and D have same X coordinate value
CD length = Yd - Yc = 4-1 = 3
Yes it does and it would also be true if the y was 4 or 6 because 2 plays into all of those but it would be false if it was something like 5
Crystal has 121 compact discs. The total number of boxes required are 5.
<u>Solution:</u>
Given, Crystal has 121 compact discs that she wants to put into boxes.
Each of the boxes that she brought home holds 25 discs.
We have to find how many of these boxes will she need for all of her discs?
Now, we know that, number of boxes required 
Here we took 5 because 0.84 means that box with discs less than 25 still we require a box.
Hence, the total number of boxes required are 5.
