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If the distance between the points (2, -2) and (-1, x) is 5, one of the values of x is

1 Answer

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We know


\boxed{\sf Distance=√((x_2-x_1)^2+(y_2-y_1)^2)}

ATQ


\\ \sf\longmapsto √((-1-2)^2+(x+2)^2)=5


\\ \sf\longmapsto √((-3)^2+x^2+4x+4)=5


\\ \sf\longmapsto √(9+x^2+4x+4)=5


\\ \sf\longmapsto √(x^2+4x+13)=5


\\ \sf\longmapsto x^2+4x+13=5^2=25


\\ \sf\longmapsto x^2+4x+13-25=0


\\ \sf\longmapsto x^2+4x-12=0


\\ \sf\longmapsto x^2+6x-2x-12=0


\\ \sf\longmapsto x(x+6)-2(x+6)=0


\\ \sf\longmapsto (x-2)(x+6)=0


\\ \sf\longmapsto x=2\:or\:x=-6

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