SOLUTION: the minute hand of a clock is 3 cm longer then the hour hand. if the distance between the tips of the hands at nine o'clock is 15 cm, how long is the minute hand (hint: draw a diag

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: the minute hand of a clock is 3 cm longer then the hour hand. if the distance between the tips of the hands at nine o'clock is 15 cm, how long is the minute hand (hint: draw a diag      Log On


   



Question 107052This question is from textbook
: the minute hand of a clock is 3 cm longer then the hour hand. if the distance between the tips of the hands at nine o'clock is 15 cm, how long is the minute hand (hint: draw a diagram) This question is from textbook

Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
The hands form a right triangle with hypotenuse=15
Let x=length of hr hand, x+3=minute hand length
x^2+(x+3)^2=15^2
x^2+x^2+6x+9=225
2x^2+6x+9-225=0
2x^2+6x-216=0
2(x^2+3x-108)=0
2(x+12)(x-9)=0
x=-12 can't be an answer (negative)
x=9 cm
x+3=12 cm length of minute hand. Answer.
Check:
9^2+12^2=15^2
81+144=225 True
Ed