Respuesta :

Answer:

2A/h   - b2=  b1

Step-by-step explanation:

A = 1/2 ( b1+ b2) h

Multiply each side by 2

2*A = 2*1/2 ( b1+ b2) h

2A =  ( b1+ b2) h

Divide each side by h

2A/h =  ( b1+ b2) h/h

2A/h =  ( b1+ b2)

Subtract b2 from each side

2A/h  - b2=  b1+ b2-b2

2A/h  - b2=  b1