<span>x^2+8x-20=0
Factor the left side of the equation
</span><span><span>(x−2)</span><span>(x+10)</span></span>=<span>0
</span>
Set the factors to both equal the number 0
<span><span>x−2</span>=<span><span><span>0
and/or
</span>x</span>+10</span></span>=<span>0
</span>x = 2 and/or x = -10
There is really nothing to know. All you have to use is context clues and common sense. We know some synonyms for direct are manage and handle. Indirect means not direct, right? And we can't handle or manage earth's interior (core), right? Therefore, the study of earth's interior is an example of indirect observation because we cannot directly manage it.
The 6th planet from the sun is Saturn. Here is a picture of all of the 8 planets from the sun.
