Question

The diagonal of a cube is 28 cm. Identify the length of an edge.

Answer 1

So the diagonal of cube
this was a practice act question so her's the answer

look at the cube through one of the faces
you will see the diagonal as the hypotonuse of  a triangle
and also a triangle on the floor (look at attachment)
the ,diagonal is 28
a^2+b^2=28^2
a=b since it is a cube
remember that this is a 45,45 triangle so therefor
a=b=x
c=x√2 so
28=x√2
divide both sides by √2
28/(√2)=x
the diagonal on the floor is 28/(√2)
the sides of the triangle form another 45 45 90 triangle with 28/(√2) as hyponuse so
a=b=x
c=x√2=28/(√2)
solve for x
x√2=28/(√2)
divide both sides by √2
same as mujlitply both sides by 1/(√2) so
28/(√2) times 1/(√2)=28/(2)=14
the answer of 1 diagonal is 14 cm
the answer is 14cm