Question

Triangle ABC is right angled at A. if AB is 20 cm and AC is 15 cm then find length of BC

Answer 1

Answer:

BC = 25

Step-by-step explanation:

To find the length of BC you need to use the pythagorean theorem.  

$a^{2} +b^{2}=c^{2}$

There are two part to a triangle that need to be put into this equation.  The hypotenuse(c) and the legs(a, b).  The legs would be the side NEXT to the right angle.  The hypotenuse is ACROSS from the right angle.  In this equation we are looking for the hypotenuse.  It doesn't matter which letter the legs replace just remember that the hypotenuse alway has to be C.

$20^{2} +15^{2} =c^{2}$

Now you have to square the numbers then add.

$400+225=c^{2}$

$625=c^{2}$

Now find the square root of 625 to get rid of the squared in the C.

c = 25

Hope this helped.