To find if something is a parallelogram, they 1 set of line segments need to have the the slope. In this equation, Slope equals x1 + x2 divided by y1 + y2 (Or the other way around, x2 + x1 divided by y2 + y1)
For your other point, it could be (-4,5)
If this is confusing, please tell me! I'll try to better explain. It also helps to draw out a graph so you can plot the points.
Answer:
{-2, 6}
Step-by-step explanation:
10-5y=20
-5y=10
y=-2
10-5y=-20
-5y=-30
y=6
Answer:
y=3.5x
Step-by-step explanation:
to find the the feet mary walks per second, divide 14 by 4
14/4=3.5 feet/second
the total distance mary walks can be represented by multiplying the number of feet she walks per second by the number of seconds she walks
y= 3.5x
in this model, x is seconds
2 1/2 = (2*2+1)/2 = 5/2
5/2 : 1/4 = 5/2 * 4/1 = 20/2 = 10
(a) 
since 13 is prime.
(b) 
, and there are 81/3 = 27 multiples of 3 between 1 and 81, which leaves 81 - 27 = 54 numbers between 1 and 81 that are coprime to 81, so 
.
(c) 
; there are 50 multiples of 2, and 20 multiples of 5, between 1 and 100; 10 of these are counted twice (the multiples of 2*5=10), so a total of 50 + 20 - 10 = 60 distinct numbers not coprime to 100, leaving us with 
.
(d) 
; there are 51 multiples of 2, 34 multiples of 3, and 6 multiples of 17, between 1 and 102. Among these, we double-count 17 multiples of 2*3=6, 3 multiples of 2*17=34, and 2 multiples of 3*17=51; we also triple-count 1 number, 2*3*17=102. There are then 51 + 34 + 6 - (17 + 3 + 2) + 1 = 70 numbers between 1 and 102 that are not coprime to 102, and so 
.
