Question 1103559

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Mary walks 20m diagonally across a rectangular field. She then returns to her starting position along the outside field. The total distance she walks is 48m.
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d, diagonal
x and y dimensions


{{{x^2+y^2=d^2}}}
{{{x+y+d=48}}}
{{{x+y=48-20}}}
{{{x+y=28}}}
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{{{x^2+y^2=20^2}}}
{{{x^2+y^2=400}}}


If you can solve this system by yourself, then you will be fine:
{{{system(x+y=28,x^2+y^2=400)}}}