How do you find the missing length for the right triangle below the short side is 9cm and the hypotenuse is 30 cm?

1 Answer
Apr 21, 2016

Answer:

28.62cm

Explanation:

The Pythagorean theorem is this: #a^2+b^2=c^2#, where #c# is the hypotenuse (which is the longest side and is opposite the right angle), and #a# and #b# are the other sides. Given the information we have, we can say that:
#9^2+b^2=30^2#, where #b# is the unknown side.
Now its a matter of rearranging and solving:
#b^2=30^2-9^2#
#b^2=900-81#
#b^2=819#
#b=sqrt(28.618)#
And if you type that into your calculator you'll get #b=28.62cm# (Don't forget units)