right triangles
TRANSCRIPT
RIGHT TRIANGLESSolution of a right triangle when two sides are known
Right angle
Triangle
A shape with 3 sides
Theorem
A mathematical formula for calculating values.
Side
Length
The measurement of the extent of something along its greatest dimension
Hypotenuse
“X square”
“Plus”
“Equal”
“Square root”
Procedure
If the length of two sides in a right-
angled triangle is known, then the
length of the third side can be
calculated using Pythagoras’ Theorem.
The first thing that we need to do is to check whether we can use Pythagoras’ Theorem or not.
Does the triangle have right angle?
Yes, it does
Are we given enough information?
Since we are looking for a side, do we have the length of the other two sides?
Yes, we do.
This rule states that the square on the hypotenuse (what we are looking for) is equal to the sum of the squares on the other two sides, or what we get when we square the other two lengths and add them together.
Using Pythagoras’ Theorem, we get:
Practice:
Say which of the following triangles is really right-angled:
A) B) C)
Find the length of the missing side
A) 10 cm B) 7 cm C) 8 cm
SUMMARY