Question

classify the triangle with the given side lengths as acute, right, obtuse, or not a triangle 21, 28, 35

Answer 1

The triangle with side lengths 21, 28 and 35 can be solved in a number of ways. We shall attempt to solve it by using the Pythagoras theorem, and if the answer turns out correct, then its a right triangle.

The Pythagoras theorem states thus;

`\begin{gathered} c^2=a^2+b^2 \\ \text{Where c is the longest side, and a and b are the other two sides} \\ \text{This means;} \\ 35^2=21^2+28^2 \\ 1225=441+784 \\ 1225=1225 \\ \text{LHS}=\text{RHS} \end{gathered}`

Since the Left hand side (LHS) equals the Right hand side (RHS), that means the given side lengths make a right angled triangle