base is the long bottom part
hiehg is the vertical bit
remember:

add exponnets when multiplying by similar base
and
(ab)(cd)=(a)(b)(c)(d)=(ac)(bd), associative
given
base=4ab²c⁷
height=3a²b⁵
A=(1/2)(4a¹b²c⁷)(3a²b⁵)
A=(2)(a¹)(b²)(c⁷)(3)(a²)(b⁵)
A=(2)(3)(a¹)(a²)(b²)(b⁵)(c⁷)
A=(6)(a³)(b⁷)(c⁷)
A=6a³b⁷c⁷