Hello!
You can use the Pythagorean Theorem to solve this
Separate the rectangle into two triangles
[tex] a^{2} + b^{2} = c^{2} [/tex]
c is the diagonal
a and b are the side lengths
Put in the values you know
[tex] 5^{2} + 4^{2} = c^{2} [/tex]
Square the numbers
[tex]25 + 16 = c^{2} [/tex]
Add
[tex]41 = c^{2} [/tex]
Take the square root of both sides
6.4 = c
The answer is B) 6.4 units
Hope this helps!
