Question

Anil is constructing a tall windmill supported by two wires 1 must be 10m and distance between the wires must be 21 m anil wanted to know what length to cut for the other wire
a. 17m
b. 11m
c. 18m
d. 30m​

Answer 1

Given:

Anil is constructing a tall windmill supported by two wires.

One wire must be $10m$ and distance between the wires must be $21m$

To find: Length to cut for the other wire?

Solution: let's consider the length to cut for the other wire $=l$

So here, the slanting side is $10m$ long,

The Vertical height of the windmill is $8m$

Let's assume the half-length of base $=x$

and the remaining portion $=y$

So total $x+y=21$

To find $x$ and $y$

Applying Pythagoras theorem,

$x^{2} +8^{2} =10^{2} \\x^{2} =\sqrt{10^{2} -8^{2} }\\x=6$($x^{2} =6^{2}$)

Now,

Again Applying Pythagoras theorem on another side of the triangle,

$y^{2} =(21-x)^{2}+8^{2} \\y^{2} =(21-6)^{2} +8^{2} \\y^{2} =15^{2}+ 8^{2}= 17^{2} \\y=17m$

So, Anil should have to cut a length of 17m for the other wire

Hence option (a)$=17m$ is correct.