Answer:
-13/4
Step-by-step explanation:
common denominator -
2*-7/2*2)+1/4=-14/4+1/4
= -13/4
Probability of getting heads: 1/2
Probability to get 2 heads out of three tries is: 1/8
Work: 1/2 x 1/2 x 1/2 = 1/8
Assuming the typewriter-looking words are the line names...
1. Line R
2. Line Q (Or R, but it is most likely Q)
3. Points E and F
Collinear Meaning: http://mathworld.wolfram.com/Collinear.html
1 and 2 are the factors its a compatable number