you need to use pythagorean theorem to figure out BD as you need the height of the triangles to figure out the area. to figure out the area of a triangle the formula is: area of triangle = 1/2 x base x height
i don’t know if you’re supposed to change the values they give you into numbers but i’m changing them
2 √ 5 = 4.47 cm
3 √ 2 = 4.24 cm
√ 2 = 1.41 cm
using pythagorus to work out BD
BD² = 4.47 ² - 4.24 ²
BD² = 2.0033
BD = √2.0033
BD = 1.42 cm
to figure out area of triangle ABD
1/2 x 4.24 x 1.42 = 3.0104 cm ²
area of BDC
1/2 x 1.41 x 1.42 = 1.0011 cm ²
total area of triangle
3.0104 + 1.0011 = 4.0115 cm ²
my answer may differ from the actual answer as the rounding will be different. i recommend you just follow my working out and but not round your numbers at the end of each step to get a more accurate answer
