<p>Hello, I would like an explanation to these two problems as I am struggling to reason through them. Thanks.</p>
<p>For #7, the fastest way is to just plug in any number and do it.
Say n =2. Do (6 x 10^-2) + (1 x 10^-2). That equals .07 which matches choice B ( 7/10^2)</p>
<p>If you have time, or you want to make sure, just check with another number.</p>
<p>For #11. You can either plug in a number and check or formulate it.
For plugging in a number, lets say you chose x = 3. So do 4(2^3) = 2^y.
You get 32 = 2^y. y must be 5. </p>
<p>Since x is 3, y is 2 more greater than x. That corresponds to Choice A. x = y -2 or
x = 5 -2 = 3</p>
<p>Or you can formulate it:
In order to multiply 4 by 2^x you have to get them to be the same base. So you do 2^2 (2^x). Which = 2^ 2+x. Now you have 2^ (2+x) = 2^y. Since they are the same base 2+x = y. rearrange and x = y - 2</p>