Raspuns :
ex 14 ) Aria trapezului = (B+b) ×h/2
= (15cm +72)×4cm/2
=87cm × 4cm / 2
=348 cm /2 = 172 cm
unde : B- baza mare
b-baza mica [ 7,2dm×10=72]
h-inaltimea
ex 15 )
Aria unui trapez dreptunghic : ( B+ b) ×h /2
= (14 cm + 26 cm ) ×8 cm /2
= 40 cm ×8 /2
=320 cm/2
=160 cm
