Answer:
X=30; Z=80; Y=70
Step-by-step explanation:
The straight lines equal 180 and you subtract 180 to 150 and 180 to 100 to get 30 and 80 and the inside of a triangle is 180 and you subtract 30 and 80 to 180 to get 70.
Negative multiply negative = Positive
Negative multiply positive = negative
Thus the answer is -4a + 16b - 12c - 12d.
The price of each stamp was $2.56 each because 100 divided by $39 is $2.56.
Hope that helped:)