If 
and 
, then you can replace 
in either equation with the equivalent expression given by the other equation. In this case, you have
and you can solve for 
.
Then 
.
For the second system, you can write
Then substitute this into the second equation and you get
so that
Step-by-step explanation:
50000 is the answer of nearest to ten thousand .
Answer:
x = ±1
Step-by-step explanation:
=> 7x² = 13-6
=> 7x² = 7
<em>Dividing both sides by 7</em>
=> x² = 1
<em>Taking sqrt on both sides</em>
=> x = ±1
A five year old can do algebra. They can if they are one of those VERY rare children. By rare children I mean their brains can process work faster than others making them able to understand it yet being so young. Also maybe because they had learned quickly they had found a algebra book and started to self teach themselves how to do that. Because if a child has a strong mind and can grasp things and learn for themselves they can learn it from looking at complete problems. Then solve them. I have seen kids be able to do math like this at a young age because they were quick at grasping the information. Also it could be that they had copied a basic formula for algebra off of a website or math book and just put their numbers in and started solving it like that. Also it could just be that they had learned it form a parent or older sibling because they were smart enough they were able to already be learning. Finally it could just be that they are a mathematical genius and were able to complete things like that themselves.
