How do you solve the system by the method of substitution? x^2-y^2=9 x-y=1

Expert Answers

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We have to solve the following system of equations by substitution.

  • x^2 - y^2 = 9
  • x - y = 1

x - y = 1

=> x = 1 + y

Substitute this for x in x^2 - y^2 = 9

=> (1 + y)^2 - y^2 = 9

=> 1 + y^2 + 2y - y^2 = 9

=> 1 + 2y = 9

=> 2y = 8

=> y = 4

x = 1 + y

=> 1 + 4

=> 5

We get x = 5 and y = 4

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