There it is i found it :)
Answer:
17 years.
Step-by-step explanation:
Zanna was born is 1997
Zanna's cousin was born in 1980
1997 - 1980 = 17
Yes because each x only has one y output
Set the 2x - 1 equal to 9 then work backwards. 2x - 1 = 9 Nine minus one is eight divided by two is four. X = 4
1) 
2) 
is a right angle (perpendicular lines form right angles)
3) 
is a right triangle (definition of a right triangle)
4) 
and 
are complementary (the acute angles of a right triangle are complementary)
