The first is a. you can rewrite it

the second is d. the only common factor between 20 and 40 that can be taken out is the 4 which becomes a 2, but inside the square roots there is still a 5 and 10, which cannot be combined
the third is c.

the fourth is d.
add 3 to both sides

then square both sides

then divide both sides by 2, x=50
<span>Ok so consider 100 divided by 11. remainder here is 1. Now consider the remainder when 100×100 is divided by 11. consider that you have one hundred hundreds, and each of them have a remainder of 1 when divided by 11. So, go through each of your hundred hundreds and divide it by 11, leaving remainder 1. Then collect up your remainders into a single hundred, and divide it by 11, leaving a remainder of 1. This process can be extended to dividing 100x100x100 by 11, and indeed, to dividing any power of 100 by 11.</span>
Remember in a geometric sequence you multiply if it is increasing if it is decreasing it is a number less than 1
Ina arthritic sequence you add if it is increasing if it is decreasing you add by a negative number
This sequence is geometric it is being multiplied by 1/2