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X^2+y^2=49 , y=7-x solve it in substitution

User Bastiflew
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2 Answers

1 vote

Final answer:

The system of equations x^2 + y^2 = 49 and y = 7 - x can be solved by substitution, resulting in the solutions (0, 7) and (7, 0).

Step-by-step explanation:

To solve the system of equations x2 + y2 = 49 and y = 7 - x using substitution, we substitute the second equation into the first one.

  1. First, we take the equation y = 7 - x and plug it into y in the first equation, becoming x2 + (7 - x)2 = 49.
  2. Simplify and solve the resulting equation x2 + 49 - 14x + x2 = 49 to 2x2 - 14x = 0.
  3. Factor out x, giving x(2x - 14) = 0. Our possible solutions for x are 0 or 7.
  4. By substituting x back into y = 7 - x, we find our solutions for y, which are 7 and 0, respectively.
  5. Therefore, the solutions to the system of equations are (0, 7) and (7, 0).

User Mark Tye
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3 votes
x^2+(7-x)^2=49
x^2+x^2-14x+49=49
2x^2-14x=0
2x(x-7)=0
x=0, x=7
User Suganth G
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7.5k points