Answer:

Step-by-step explanation:
Given

Required
Determine an equivalent expression
Express 81 as 

Apply law of indices






Hence:

Answer:
2
Step-by-step explanation:
10/16 ÷ 5/16
0.625 ÷ 0.3125
2
Step-by-step explanation:
1. a² - ( b ² - 2bc + c² ) = a ² - b ² + 2bc - c²
2. 8p² - 18 q²
3. 3ab² - c²d + 3ab - b²c²
4. x² - 2x + 1
Its a squared + xb squared = c squared so its 11 squared + 11 squared equals c squared. So I'm gonna take it down to the next step and say 11x11+ 11x11= c squared, then you end up with 121+121= c squared then you add those two and end up with 242= c squared, so then you find the square root of 242 so you should end up with 15.5 and the number goes on and on and on