Your question is non-specific so I hope that you are looking for a straightforward version. The area of a right-angled triangle is calculated the same way as any other triangle's area if the information given relates to the length and breadth.
There is a base (b) and a perpendicular height (h).
In a right angles triangle the height is perpendicular anyway because of the right angle which means the angle is 90 degrees and so it is perpendicular to the base.
Area of a triangle is always `times (1/2)`
`therefore A = (1/2)b times h` cm`^2` or in`^2` etc. depending on the measurement you are using.
To find the area of a right triangle, use the formula
where A is the area and a and b are the lengths of the sides that form the right angle.