To Euclid, a postulate is something that is so obvious it may be accepted without proof.
A. A straightedge and compass can be used to create any figure.
That's not Euclid, that's just goofy.
B. A straight line segment can be drawn between any two points.
That's Euclid's first postulate.
C. Any straight line segment can be extended indefinitely.
That's Euclid's second postulate.
D. The angles of a triangle always add up to 180.
That's true, but a theorem not a postulate. Euclid and the Greeks didn't really use degree angle measurements like we do. They didn't really trust them, I think justifiably. Euclid called 180 degrees "two right angles."
Answer: B C
1.7/1.9 = 0.894 (rounded)
Answer:
An apple costs $2.25. A mango costs $1.25.
Step-by-step explanation:
Let a = price of 1 apple.
Let m = price of 1 mango.
Cameron:
4 apples + 7 mangoes ----> total $17.75
4a + 7m = 17.75
Gavin:
2 apples + 5 mangoes ----> total $10.75
2a + 5m = 10.75
We have a system of 2 equations in 2 unknowns.
4a + 7m = 17.75
2a + 5m = 10.75
We can use the elimination method to eliminate the variable <em>a</em>. Rewrite the first equation. Multiply both sides of the second equation by -2 and write below it. Then add the equations.
4a + 7m = 17.75
(+) -4a - 10m = -21.5
---------------------------------
-3m = -3.75
Divide both sides by -3.
m = 1.25
<em>A mango costs $1.25.</em>
Now we use the first equation and substitute 1.25 for <em>m</em> and solve for <em>a</em>.
4a + 7m = 17.75
4a + 7(1.25) = 17.75
4a + 8.75 = 17.75
4a = 9
a = 2.25
<em>An apple costs $2.25.</em>
Answer: An apple costs $2.25. A mango costs $1.25.
Answer:
'A' is true; theoretically, 50% of the data items reside between the first and third quartiles (40 and 67.5)
Step-by-step explanation:
Range is 84-28 which is 56
Median is 51
1.5 x Interquartile Range (IQR) = 1.5(67.5-40) which equals 41.25
Q1 is 40
Q1 - IQR = -1.25
Low outliers are below -1.25 - 41.25; there are not data items below -42
All of them are, except ' π ' (pi) ... which gives you an idea of why
that one is usually written as a symbol and not as digits.
Here's a useful factoid regarding the other numbers on the list:
-- <em>ANY</em> number that you can write down on paper, <u>completely</u>,
using digits, is a rational number.
