What is the measure of XYZ?

To solve the system of equations below, pedro isolated the variable y in the first equation and then substituted it into the second equation. what was the resulting equation? { 5y=10x {x^2+y^2=36

The midpoints of the sides of the large square are joined to form a smaller square. what is the area of the smaller square

Zahra wants the equation below to have an infinite number of solutions when the missing number is placed in the box.