Problem 1

what is the area of the rectangle?
the minimum area of the triangle satisfied these conditions?

part 1

so the area of a rectangle is

xy=12

part 2

Problem 2

find the radius of biggest circuit

take first two circuits
hypotenuse of both are collinear

Problem 3

a cable of 80 meters hanging from the top of two poles there are two 50 meters from the ground
what is the distance from two poles if center of cable 20 meters above the ground ?

Problem 4

find the area of the red segments