Lesson 12.6: Help for Exercises 35 and 36 on page 764
In each exercise, notice that the intersection of the sphere and the plane is a circle. You are asked to find the area of the circle. Look at the diagram and locate the circle and its radius, the measurement you will need in order to find area .
In Exercise 35, you can use the Pythagorean Theorem to find y, then use y to calculate area.
In Exercise 36, you can use the Pythagorean Theorem to find z. Then think about how z is related to the radius of the circle whose area you need to find. What do you know about all the radii of a sphere?