Answer:
see explanation
Step-by-step explanation:
Using 
= i, then i² = ( )² = - 1
and i³ = i² × i = - 1 × i = - i
also
= i² × i² = - 1 × - 1 = 1
We can surmise that i raised to any multiple of 4 will equal 1
Given
( note 35 = 32 + 3 and 32 is a multiple of 4 ), thus
= 
= 1 × i³ = - i
For every 21 minutes that people spend using their cell phone, the number of texts they send increases by 5.
(I just did the test)
4m - 7n = 10
2m + 2n = 4 - multiply everything by -1.
4m - 7n = 10
-2m - 2n = -4 Add the 2 equations
(4m - 7n = 10)
+(-2m - 2n = -4)
-------------------------
2m - 9 n = 6.
The value of 2m - 9n would be 6.
