Question 1208192
3a+5b=3, a+2b=13
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They want you solve this system of two equations

    3a + 5b =  3,     (1)

     a + 2b = 13.     (2)


There are different methods for it.


I will show here the SUBSTITUTION method.


From equation (2), express  a = 13 - 2b.  

Substitute this expression for "a" into equation (1).  You will get

    3*(13-2b) + 5b = 3.


It is a single equation for a single unknown "b". 
Simplify it and find  "b"

    39 - 6b + 5b = 3,

    39 - b = 3,

    39 - 3 = b,

    b   = 36.


Substitute this value b = 36 into equation (2) and find "a"

    a + 2*36 = 13,

    a + 72 = 13,

    a = 13 - 72 = -59.


Thus a= -59, b= 36 is the unique solution to the original system.    <U>ANSWER</U> 


You may check that each equation (1) and (2) becomes an identity, when you substitute a= -59, b= 36 there.

This check confirms that the found values are correct solutions.
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Solved.