Step-by-step explanation:
the area is
A = length × width
A-old = length-old × width-old
A-new = length-new × width-new
length-new = length-old × 8
width-new = width-old × 8
=>
A-new = length-old × 8 × width-old × 8 =
= length-old × width-old × 8 × 8 =
= A-old × 8²
so, the area changes by a factor of 8² or 64.
