Step-by-step explanation:
Draw a picture of the tetrahedron. Pick a point K on the line AB, then draw a triangular plane connecting the points K, C, and D.
The intersection of plane KCD and plane ABC is the line KC.
The intersection of plane KCD and plane ABD is the line KD.
The intersection of plane KCD and plane ACD is the line CD.
The intersection of plane KCD and plane BCD is the line CD.
Answer:
Proved
Step-by-step explanation:
Solving (a):
Let the numbers be:
Their sum is:
Collect Like Terms
Divide sum by 3.
<em>Hence, this is true because there is no fractional part after the division</em>
<em></em>
Solving (b):
Let the numbers be:
Their sum is:
Collect Like Terms
Divide sum by 5.
<em>Hence, this is true because there is no fractional part after the division</em>
<em></em>
Solving (c):
Let the numbers be:
Their sum is:
Collect Like Terms
Divide sum by 4.
Split
<em>The 1.5 means that the sum can not be divisible by 4</em>