Answer:
9.5 inches
Step-by-step explanation:
The relationship is presumed to be ...
(first week's growth) + (second week's growth) = (growth in two weeks)
(first week's growth) + 3.43 inches = 12.93 inches . . . . . fill in the numbers
Subtract 3.43 from both sides of the equation:
first week's growth = 12.93 inches - 3.43 inches
first week's growth = 9.50 inches
The plant grew 9.50 inches in the first week.