We are given a right-angled triangle with one angle equal to $10^\circ$. We need to find the size of the angle $c$.

1. Problem Description

We are given a right-angled triangle with one angle equal to $10^\circ$. We need to find the size of the angle $c$.

2. Solution Steps

The sum of the angles in any triangle is $180^\circ$.

We are given a right-angled triangle, which means one of the angles is $90^\circ$.

We are also given one of the other angles as $10^\circ$.

Let the unknown angle be $c$.

So, we have:

$c + 90^\circ + 10^\circ = 180^\circ$

$c + 100^\circ = 180^\circ$

$c = 180^\circ - 100^\circ$

$c = 80^\circ$

3. Final Answer

The size of angle $c$ is $80^\circ$.