1. [12pts] Let LaTeX: \mathcal TT be the triangular region in the LaTeX: xyx y-plane with vertices LaTeX: (0,0), (m,0), (m, n) ,( 0 , 0 ) , ( m , 0 ) , ( m , n ) , where LaTeX: m, nm , n are positive constants. Use a double integral in polar coordinates to calculate the average value of the LaTeX: xx-coordinate, taken over all points in LaTeX: \mathcal T T. You may assume the formula for the area of the triangle.

step-by-step explanation:

given perimeter: 28cm

length: 9cm

atp,

2(l+w)=p of the reactangle

2(9+x)=28

18+2x=28

2x=28-18

x=10/2

x=5

therefore width is 5 cm

rick has $1400 and sally has $1500

step-by-step explanation:

to find amount of money rick has after 10 years :

principal = $1000 , time = 10 years , rate = 4% annually

to find amount of money sally has after 10 years :

her friend gives to pay her $50 per year, therefore money she has after 10 years = 50 × 10 = $500

also, sally gets $1000 after 10 years,

therefore, total amount of money sally has after 10 years = 500 + 1000 = $1500

so, after 10 years : rick has $1400 and sally has $1500