Now, try one on your own.

Solve using substitution:  set of two equations: x^2 + y=3; y = 3x+5

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x2 + y = 3   The first equation
x2 + (3x + 5) = 3   Substitute (3x + 5) for y
x2 + 3x + 5 – 3 = 3 – 3   Substract 3 from both sides of the equation
x2 + 3x + 2 = 0   Simplify
(x + 2)(x + 1) = 0   Factor
x = -2                       or x = -1 Solve each factor for x
     
y = 3(-2) + 5 = -1 y = 3(-1) + 5 = 2 Substitute the x-values into the second equation to find y
     
The solutions are (-2, -1) and (-1, 2)    
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Now, write a journal entry in your notes describing the type(s) of situations in which substitution would be a more appropriate method than tables or graphs for solving a system of equations.