6.3 ANSWERS which level of difficulty should you choose?

a) Check whether y = 17 when x = 3.

y = 2 ^. 3² - 1 

y = 2 ^. 9 - 1 

y = 18 - 1 

y = 17 

So, y = 17 when x = 3. 

b) Which y belongs to x = -4

y = 2 ^. (-4)² - 1 

y = 2 ^. 16 - 1 

y = 32 - 1 

y = 31 

So, with x = -4, y = 31