What is the exact side length of a square that has a diagonal length of 12 inches

Can someone me my sister? she is in third grade. 50 points and brainlist! ones that are not answered. plz and thx!

What is the solution set of the quadratic inequality x^2-5< or equal to 0

Identify the function that contains the data in the following table: x     -2         0         2         3         5     f(x)     5         3         1         2         4     possible answers: f(x) = |x| + 1 f(x) = |x - 2| f(x) = |x - 2| - 1 f(x) = |x - 2| + 1