SOLUTION: solve the system by the method of substitution x=y+3 x=y^2+1

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Question 927944: solve the system by the method of substitution
x=y+3
x=y^2+1
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
x=y%2B3.....eq.1
x=y%5E2%2B1...eq.2
______________
x=y%5E2%2B1...eq.2 substitute x=y%2B3
y%2B3=y%5E2%2B1...solve for y
0=y%5E2-y-3%2B1
y%5E2-y-2=0
y%5E2%2By-2y-2=0
%28y%5E2%2By%29-%282y%2B2%29=0
y%28y%2B1%29-2%28y%2B1%29=0
%28y-2%29%28y%2B1%29=0
solutions:
if %28y-2%29=0=> y=2
if %28y%2B1%29=0=> y=-1
now find x:
x=y%2B3.....eq.1 if y=2
x=2%2B3
x=5
x=y%2B3.....eq.1 if y=-1
x=-1%2B3
x=2
so, your solutions are:
(5,2)
and
(2,-1)