Answer:
Step-by-step explanation:
We can solve this question using proportion
Perimeter of the square/Time is takes to unlock
We are told in the question that:
The cellphone unlocks when the perimeter reaches 32 centimeters, taking a total of 2.5 seconds.
Hence, the perimeter of the square after 1.5 seconds is:.x = unknown
32/2.5 = x/1.5
Cross Multiply
2.5x = 32 × 1.5
x = 32 × 1.5/2.5
x = 19.2 centimeters
Answer:
D
Step-by-step explanation:
7^-2 = 1/7^2
The negative means you flip it
1/7^2 times 7^6 is 7^6/7^2 (just multiply).
using rules of exponents, 7^6/7^2 is 7^4 (just subtract 2 from 6)
D is the only one that equals 7^4, as 2 times 2 is 4.
