i need help i’m failing math!!!

Answer:
[tex]\huge\boxed{\bf\:2\sqrt{5} \:\: units }[/tex]
Step-by-step explanation:
We have a figure given in the shape of a square with a diagonal (x) passing from one edge to another. We need to find the measure of its diagonal if the side of the square is [tex]\sqrt{10}[/tex] units.
We know that, a square has all equal sides. Then, all the sides of the square will be equal to [tex]\sqrt{10}[/tex] units.
Now, let's find the diagonal.
To find the diagonal of a sqaure from one of its sides, we need to know the formula ⟶ Diagonal = side [tex]\bf\:\sqrt{2}[/tex].
By using this formula,
[tex]Diagonal (x)\\= side *\sqrt{2} \\= \sqrt{10} *\sqrt{2}\\ = \sqrt{5*2*2} \\= \boxed{\bf\:2\sqrt{5} \:units}[/tex]
→ The diagonal of the square = 2√5 units.
[tex]\rule{150pt}{2pt}[/tex]