Problema Solution
A 17 foot long support wire for a radio tower stretches from its mooring point on the tower to a point on the ground x feet from the base of the tower. The height at which the wire attaches to the tower is 7 feet more than the distance from the base of the tower to its anchor on the ground. At what height does the wire attach to the tower?
(a) If x represents the distance on the ground that the wire reaches. Write an expression for the height the wire attaches to the tower.
(b) At what height does the wire attach to the tower?
Answer provided by our tutors
The height at which wire attaches ==> (x+7) = √(172-x2)
x2+(x+7)2=172
=> x2+x2+14x+49=289
=> 2x2+14x-240=0
=> (x-8)(x+15)=0
So, x=8 or x=-15;
x=-15 not possible. So x=8.
The wire attaches to the tower at 8+7 =15 feet.