Question 397249

A Square has all sides same; let the side be {{{a}}}

a diagonal {{{d = 7cm}}}

a diagonal divides a square into two right triangles, so we will use Pythagorean Theorem to find {{{a}}}

{{{d^2 = 2a^2}}}

{{{(7cm)^2 = 2a^2}}}

{{{49cm^2 = 2a^2}}}

{{{49cm^2/2 = a^2}}}

{{{24.5cm^2 = a^2}}}

{{{a = sqrt(24.5cm^2) }}}.........we can round it to {{{sqrt(25cm^2)}}}

{{{a = sqrt(25cm^2) }}}

{{{a = 5cm }}}

the area will be:

{{{A = a^2}}}

{{{A = (5cm)^2}}}

{{{A = 25cm^2}}}