Wednesday+February+17,+2010Set3

Worksheet on Word Problems!

Problem 2 Danny a)The variables are feet above water, and seconds with seconds being x and feet above water being y the ordered pairs are (0,105), (5, 30) and (10,21) equation=(66/50)x^2-(108/5)x+105 b)plug 4 in for x and you get 39.72 plug 15 in for x and you get 78 c)find the vertex-->-b/2a x=8.1818 then plug in system and y equals 16.6363, and 16.6363 is the lowest point, and it occurs as 8.1818 seconds. d)plug 200 in for Y and you get 19.96790513

Problem 3 Ryan y=a*b^x the two ordered pairs are (0,30) and (4,18) (min,psi) a) 18=30*b^4 b=3/5^1/4*^x= b= 3/5^x/4 y=30*3/5^x/4

b) y=30*3/5^12/4 y=6.48 therefore 6.48psi>5psi so you will be able to make it home.

Problem 4 Lacey

a) x=years since harvesting began (in 2005) y=number of stalks harvested (0, 10) a=10 (2, 30) y=ab^x y=10b^x 30=10b^2 3=b² b=√3 y=10(√3)^x

b) 100=10(√3)^x 10=(√3)^x log 10=(x) log √3 x=log 10/log √3 x=4.192 years

c) According to this model, Brighton Erly harvested her first stalk in 2005, along with 9 others. d) x=520 y=10(√3)⁵²⁰ y=overflow

An incredibly large amount of stalks!