A rectangular pond measures 3 m by 5 m. A concrete walkway of uniform width is constructed around the pond. If the walkway and pond together cover an area of 35 m2, how wide is the walk? (hint: draw a picture)

The walk is meter(s) wide.

2 m

Step-by-step explanation:

A=35

l=3+x

w=5+x

A=l*w

(3+x)(5+x)=35

15+3x+5x+x² = 35

x²+8x-20=0

x=2, -10

it cant have a negative length so x=2

hello from mrbilldoesmath!

answer:

a(n) - a(n-1) -3

discussion:

this ones a bit interesting. given a(n) = 5 - 3n consider this:

a(n-1) = 5 - 3(n-1)

          = (5 - 3n) + 3             => but a(n) = 5 - 3n, the first term

          = a(n)   + 3                 => subtract 3 from both sides

a(n-1) -3 = a(n)  

or

a(n) - a(n-1) -3

you,

mrb