Complete the square. Pls help me

Two sides of a triangle mesure 20cm and 30cm. what is the measure of the third side

The frequency table shows a set of data collected by a doctor for adult patients who were diagnosed with a strain of influenza. patients with influenza age range number of sick patients 25 to 29 30 to 34 35 to 39 40 to 45 which dot plot could represent the same data as the frequency table? patients with flu

Aquadrilateral has exactly 3 congruent sides davis claims that the figure must be a rectangle why is his claim incorrect.