A point is , as seen in ry1, the limiting dimensionless case of circles (or any other shape) as the dimension gets smaller and smaller .
A line segment is really the shortest distance between two points.
From two different points passes a line.
From three different points not on a line, pass two lines.
D, E and G are on the same line .
For A there are 6 choices; After A, for B 5 choices; For C 4 ;
For D 3 choices but 2 of them are the same.
So the result should be the sum of natural numbers up to 6, minus 1
The adjacent angles, in this case, form a direct angle .
The angles smaller than 90 degrees are called acute .
The angles greater than 90 degrees are called obtuse .
Obviously rechtangle .
Parallel lines do never intersect (or they intersect at infinity) .
A line can not intersect itself.
Two nonparallel lines do certainly intersect somewhere .
1st linee finds 6 lines to intersect, next finds 5, next 4 ... .
Since no parallel lines no. of intersection points 1+2+3+4+5+6
There may be order of infinities ... .
S
Be careful with DD' and AA' .
Just to teach . Some people tend to use a notation inheriting from set thory (open, half open and closed sets). They prefer [AA'] , [BB') and (CC').
congruent is equal in size and shape .
similar is equal in shape .
The adjacent angles to it are 62 degrees .
62 degrees show that DC and BA are parallel .
Then BC intersects two parallel line segments .
The statement given will be proven later but towards left we have 62 deg. and 50 deg. and towards right 92 deg. and the angle with question mark .
All may but we will use I and III for their simplicity .
They all add up to 180 degrees .
At a vertex at least two lines cross .
In the evening, when the prof and his wife are on the phone again, she asks:
"I don't understand it. When you count, you get 39, and when they do, they get 40.
That's more than strange..."
"Well", the prof says. "This is a cordless phone, so
you can stay on the line and count with me: zero, one, two, three,..."
This joke is to remind you of two facts:
1. "Zero" is nor a conting number !
2. Points, lines, planes etc. are just thought objects !
3 x m(< B) = 153 => m(< B) = ...
Till the hour-hand makes two turns the vane makes makes 24 full turns.
If the hour-hand stood still, there would be 2x24 = 48 right angles.
One endpoint may be common between 2 line segments .
Rays may use the 3 endpoints of the line sagments as endpoints.
Sum of them must be 50 deg. and they are equal. Look please at ry1 .
Any part of a line has infinite no. of points .
Interior opposite angles are equal .
Which is FALSE is being asked .
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