Practice Test 8

All points $(x,y)$ that are 5 units from the point $(1,2)$ form a circle. Write the equation of this circle in standard form. (Use the Pythagorean Theorem/distance formula.)

A cell tower is located at $(3,4)$ on a coordinate grid. Its signal reaches all points within $10$ units of the tower. Write the equation of the circle representing points exactly $10$ units from the tower.