Answer:
Step-by-step explanation:
Let's solve this problem step-by-step. The library had 1,500 books in 2011. The ratio of books in 2011 and in 2012 is 1:2. Therefore, let the number of books in 2012 be 
.
We have the following proportion:
Therefore, there were 3,000 books in 2012. The ratio of books in 2012 and in 2013 is 2:5. Let the number of books in 2013 be 
.
We have:
Therefore, there were 7,500 books in 2013.
Answer:
x = 13.5
y = 7
(13.5,7)
what the solution means is that (13.5,7) would be the point at which the two lines, x+y=20.5 and x-y=6.5, would intersect
Step-by-step explanation:
x + y = 20.5
x - y = 6.5
if we add the two equations we get:
2x = 27
x = 13.5
y = 20.5 - 13.5
y = 7
solution as an ordered pair:
(13.5,7)
What the solution means is that (13.5,7) would be the point at which the two lines, x+y=20.5 and x-y=6.5, would intersect
Answer:
4
Step-by-step explanation:
a=3
b=1
c=-1
(b + c) - (c-a)
(1+(-1))-((-1)-(3))
Note
+*-= -
+*+=+
-*-=+
So
(1-1)-(-1-3)
0-(-4)
4
Answer:
Step-by-step explanation:
Angle 9 = 85 degrees
Angle 9 and < 11 are vertical angles
Vertical angles are equal
<11 = 85 degrees
