Question

If the sides of a square are lengthened by 7 cm, the area becomes 121 cm^2.
Find the length of a side of the original square

Answer 1

solve
\[(x+7)^2=121\]
\[x+7=11\]
\[x=11-7=4\]

Answer 2

x = length of a side of the original square

Lengthen the sides by 7 cm
area = 121 cm²
(x+7)² = 121
x+7 = √121
x+7 = 11
x = 4

original square was 4 cm by 4 cm