The explicit formula for given sequence is: 
Step-by-step explanation:
Given sequence is:
-1,4,-16,64.....
We can see that there is no same difference between consecutive terms so we will find common ratio to see if it is a geometric sequence.
Here

The explicit formula for geometric sequence is:

Putting the values of r and a1

Hence
The explicit formula for given sequence is: 
Keywords: Geometric sequence, common ratio
Learn more about geometric sequence at:
#learnwithBrainly
Scalene triangles. I think
Answer:
Delivery cost per minute = $0.3 per minute
Step-by-step explanation:
Given:
Cost of pizza = $12
Total amount pay by Ruby = $15
Time taken for delivery = 10 minutes
Find:
Delivery cost per minute
Computation:
Total amount of delivery = Total amount pay by Ruby - Cost of pizza
Total amount of delivery = 15 - 12
Total amount of delivery = $3
Delivery cost per minute = Total amount of delivery / Time taken for delivery
Delivery cost per minute = 3 / 10
Delivery cost per minute = $0.3 per minute
Answer:
it is 7squere meters
Step-by-step explanation:
Ralph is 12. If Ralph is 12 that means Sara is 4 (12/4=3). In 4 years Sara will be 8 and Ralph would be 16 (16/8=2).