How should we write the solution of the system of equations

Drag the tiles to the correct boxes to complete the pairs. not all tiles will be used. the heights of the girls in an advanced swimming course are 55, 60, 59, 52, 65, 66, 62, and 65 inches. match the measures of this data with their values.

[10 points, algebra 2-simplifying complex fractions]according to my answer key the restrictions are -1 and 4. but why not positive 1?

The distance of a chord from the centre of a circle is 12cm and the lenght of the chord is 10cm. find the radius of the circle