Question

What is the area of triangle RST?

Answer 1

What I usually do is to Separate the triangle into two in order to get two 90° triangle. So, the first one is triangle RUT and second is triangle SUT.
Area of triangle= 1/2 × length × width
Based on the graph, the dimension of a square is 1unit×1unit.
Area of triangle RST = Area of RUT + Area of SUT
=( 1/2 × 3 × 2)+(1/2 ×3×4)
=9 unit^2

Answer 2

The area of triangle RST is 9 square units.

Explanation:

Area of a triangle is

`A=(1)/(2)* base* height`

The area of triangle RST is the sum of area of triangle RTU and STU.

From the given graph it is clear that, in triangle RTU, base RU=2 units, height TU=3 units. The area of triangle RTU is

`A=(1)/(2)* 2* 3=3`

In triangle STU, base US=4 units, height TU=3 units. The area of triangle STU is

`A=(1)/(2)* 4* 3=6`

The area of triangle RST is

`Area(\triangle RST)=Area(\triangle RTU)+Area(\triangle STU)`

`Area(\triangle RST)=3+6=9`

Therefore the area of triangle RST is 9 square units.