Answer:
AD = 23
Step-by-step explanation:
Y^2-9^2
(y-9)(y+9)
To see if its right:
y*y+y*9-9*y-9*9
y^2+9y-9y-81
y^2-9^2
Answer:
123
Step-by-step explanation:
s=-2
-15s^2-9(-5+s)
=-15s^2+45-9s
=-15s^2-9s+45
=15(-2)^2-9×(-2)+45
=15×4+18+45
=60+18+45
=123
Answer:
Nitrogen
Step-by-step explanation:
Nitrogen and oxygen are by far the most common; dry air is composed of about 78% nitrogen (N2) and about 21% oxygen (O2). Argon, carbon dioxide (CO2), and many other gases are also present in much lower amounts; each makes up less than 1% of the atmosphere's mixture of gases. Hope this helped!
