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Thursday, November 6, 2014

Solving Quadratic Equations of Two Unknowns, 2

Category: Algebra

"Published in Newark, California, USA"

Solve the following systems by substitution:



Solution:

Consider the given equations above 



Rewrite the second equation in terms of y at the left side as follows




Substitute the value of y to the first equation, we have









By using quadratic formula, the values of x are


 
 
 

If you will choose the positive sign, then the value of x is





Substitute the value of x to the second equation in order to get the value of y, we have



 



If you will choose the negative sign, then the value of x is






Substitute the value of x to the second equation in order to get the value of y, we have 





Therefore, the solutions of the two equations are:  

 

Wednesday, November 5, 2014

Solving Quadratic Equations of Two Unknowns

Category: Algebra

"Published in Newark, California, USA"

Solve the following systems by elimination:



Solution:

Consider the given equations above



Multiply the first equation by 2 and the second equation by -1, we have



Add the two equations in order to solve for the value of y.


----------------------------


Substitute the value of y to either of the two equations in order to solve for the value of x, we have







Therefore, the solutions of the two equations are: