Problema Solution
A manufacturer makes circular targets that have an area of 25 ft2. According to competition rules, the area can be in error by no more than 0.25 ft2. Use an absolute value inequality to find the acceptable range of values for the radius.
Answer provided by our tutors
let r be the radius of the circular target
since the area of the circular target is A= r^2*pi
according to competition rules, the area can be in error by no more than 0.25 ft2
|A - 25| <= 0.25
|r^2*pi - 25| <= 0.25
-0.25 <= r^2*pi - 25 < = 0.25
-0.25 + 25 <= r^2*pi < = 0.25 + 25
24.75 <= r^2*pi < = 25.25 divide both sides by pi
24.75/pi <= r^2 < = 25.25/pi
for pi = 3.14
2.8075 <= r <= 2.8357