Answer:
9 and 10
side length = 9.5 ft (nearest tenth)
Step-by-step explanation:
Area of a square = s² (where s is the side length)
Therefore, if the square garden measures 90 ft², the length of one side will be √90.
To find the two whole numbers that √90 lies between, find the perfect square either side of 90.
Perfect squares: 1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144, ...
Therefore, 90 lies between 81 and 100:
⇒ 81 < 90 < 100
Square root the numbers:
⇒ √81 < √90 < √100
⇒ 9 < √90 < 10
Therefore, the length of one side of Grandma's garden is between 9 and 10.
To estimate √90 to the nearest tenth, find the difference between the three numbers:
[tex]81 \overset{+9}{\longrightarrow} 90 \overset{+10}{\longrightarrow} 100[/tex]
As 90 is almost in the middle of 81 and 100,
⇒ √90 = 9.5 (nearest tenth)
According to the calculator, √90 = 9.486832981... = 9.5 (nearest tenth)
which verifies the estimation.
