Respuesta :

Answer:

b = 3 units

Step-by-step explanation:

Area of a parallelogram = base × height

Thus,

Area = 21 units²

base = b

height = 7

Plug in the value into the formula

Thus:

21 = b × 7

Divide both sides by 7

21/7 = b

3 = b

b = 3 units