Find the sum and choose the correct answer. 2n 3 + 4n 2 - 7 and -n 3 + 8n - 9 -n3 - 4n2 - 8n - 16 n3 + 4n2 + 8n - 16 n3 + 4n2 + 8n + 16 3n3 + 4n2 + 8n - 2

Option B (n³ + 4n² + 8n - 16)

Step-by-step explanation:

In this question we have to add two expressions given

( 2n³ + 4n² - 7 ) and ( -n³ + 8n - 9 )

( 2n³ + 4n² - 7 ) + ( -n³ + 8n - 9 )

Now we group the similar terms

( 2n³ - n³ ) + 4n² - ( 7 + 9 ) 8n

= n³ + 4n² - 16 + 8n

= n³ + 4n² + 8n - 16

Option B (n³ + 4n² + 8n - 16) is the correct answer.

10.416 meters per second

step-by-step explanation:

distance=1 00 meters

time= 9.6 seconds in decimal form or 9 3/5 as a mixed number

average speed= 100/9.6

=10.416 meters per second or 10 52/125 as a mixed number.

12

step-by-step explanation:

12 + 5 = 17

12x2=24

24-7=17