We could determine the length of side BC using pythagoras, if the square numbers of perpendicular sides add up, the result is the square of the hypotenuse
BC² = 7² + 7²
BC² = 49 + 49
BC² = 49 × 2
BC = [tex] \sqrt{49 \times 2} [/tex]
BC = √49 × √2
BC = 7√2
The answer is first option
