Given that r is the midpoint of qs and that the lenght of qr is 5.7, find the lenght of qs

We know that the midpoint is the a point in the center of the line (r). This means that from the midpoint to the endpoint (qr) is half the length of the overall line. This means that 5.7 (the length of qr) units is half the length of the line. Two halves make a whole so 5.7 × 2 = 11.4 units as the length of the entire line qs.
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