Posted by nelly on .
a piece of wire measuring 20 feet is attached to a telephone pole as a guy wire. the distance along the ground from the bottom of the pole to the end of the wire is 4 feet greater than the height where the wire is attached to the pole. how far up the pole does the guy wire reach?

algebra 
Shawn,
The guy wire, the telephone phone and the ground form a rightangled triangle.
Your measurements are x, x+4, and 20.
To solve for x, you could use the Pythagorean Theorem, a^2+b^2=c^2.
Let a=x
Let b=x+4
Let c=20
First, plug in the values for a, b and c, and then simplify.
From here, solve for x by either factoring, or using the quadratic formula (I'm going to use the quadratic formula).
Now, plug in the values of x into the original formula
The measurement of the telephone pole is x.
My values of x are 12 and 16.
If we substitute the values of x in,
only x=12 makes sense,
because a telephone pole with height 16 is impossible
hope it helps.