Calculating the Area of a Kite in a Figure

[chawki]

Homework Statement

The lengths of the two perpendicular supporting rods are 80.0cm and 105.0 cm. The lengths of the two shorter sides are 50.0 cm and the lengths of the two longer sides are 85.0cm.
The supporting rods are drawn with a bolded line in the figure.

Homework Equations

Calculate the area of the kite in the figure and give the answer in units meters squared.
The supporting rods are drawn with a bolded line in the figure.

The Attempt at a Solution

we divide the kite into two triangles, the up triangle and lower triangle
A_kite=A_up+A_down

A_up= 0.8*0.3/2 = 0.12m²
A_down= 0.8*0.75 / 2 = 0.3m²

Akite= 0.12+0.3 = 0.42m²

 

[Mark44]

Homework Statement

The lengths of the two perpendicular supporting rods are 80.0cm and 105.0 cm. The lengths of the two shorter sides are 50.0 cm and the lengths of the two longer sides are 85.0cm.
The supporting rods are drawn with a bolded line in the figure.

Homework Equations

Calculate the area of the kite in the figure and give the answer in units meters squared.
The supporting rods are drawn with a bolded line in the figure.

The Attempt at a Solution

we divide the kite into two triangles, the up triangle and lower triangle
A_kite=A_up+A_down

A_up= 0.8*0.3/2 = 0.12m²

Where did the 0.3 come from? Apparently you are saying that the altitude of the upper triangle is 30 cm or 0.3 m. How did you get that?

A_down= 0.8*0.75 / 2 = 0.3m²

Here you are apparently saying that the altitude of the lower triangle is 75 cm of .75 m. How did you get that?

Akite= 0.12+0.3 = 0.42m²

 

[chawki]

Where did the 0.3 come from? Apparently you are saying that the altitude of the upper triangle is 30 cm or 0.3 m. How did you get that?
Here you are apparently saying that the altitude of the lower triangle is 75 cm of .75 m. How did you get that?

we try to find the heigh of the upper triangle, we have
0.4²+h²=0.5²
h²=0.5²-0.4²
h=0.3m

and then it's easy to find the area of that upper triangle..

 

[Mark44]

OK - your answer in post #1 looks fine.