Since you're adding x feet to the length which is 12 feet:
New area: (12+x)10.5
To estimate this I find it easy to turn the fractions into decimals and then you can easily estimate. To turn a fraction into a decimal divide the numerator by the denominator.
78.8 rounded to the nearest tenths is 78.8
We can not round it to the tenths because it already is rounded to the tenths.
Answer:
x=2/5
Step-by-step explanation:
