find the area of the figure

Answer:
Step-by-step explanation:
It's a trapezoid.
The formula of an area of a trapezoid:
[tex]A=\dfrac{b_1+b_2}{2}\cdot h[/tex]
b₁, b₂ - bases
h - height
(look at the picture)
Use the Pythagorean theorem to calculate the length x:
[tex]x^2+12^2=15^2[/tex]
[tex]x^2+144=225[/tex] subtract 144 from both sides
[tex]x^2=81\to x=\sqrt{81}\\\\x=9[/tex]
Substitute:
[tex]b_1=9+12+9=30\\b_2=12\\h=12[/tex]
[tex]A=\dfrac{30+12}{2}\cdot12=(42)(6)=252[/txt]