Answer:
225
Explanation:
length of side in square 3 = 36/4
=9
length of side in square 2 = 48/ 4
= 12
using pythagorus theorem you can find side of square 1
take the triangle between 3 and 2
9^2 + 12^2 = length of side 1^2
81 + 144 = l^2
225 = l^2
l = 15
therefore length of side 1 is 15
area of square 1 = 15^15
area = 225 square units
hope this helped
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