SOLUTION: Help!! I have a test on Friday and do not understand how to do this type of problem. Please include all steps so I can understand how to apply for other problems. Thank you 1

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Question 110105This question is from textbook algebra Structure and method book 1
: Help!! I have a test on Friday and do not understand how to do this type of problem. Please include all steps so I can understand how to apply for other problems. Thank you
1. A rectangular piece of plywood is trimmed to make a square by cutting a 4-cm strip off the top and a 2-cm strip off one side. If the area of the original piece is 74 cm^2 (cm squared) greater than the area of the square, find the dimensions of the rectangle.
2. A small city park consists of a rectangular lawn surrounded on all sides by a 330m^2 ( m squared) border of flowers 2.5 m wide. Find the area of the lawn if the entire park is 5 m longer than it is wide.

Thank you!!! SISI
This question is from textbook algebra Structure and method book 1

Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
A) L*w=a
B) (L-4)(w-2)=a-74
C) L-4=w-2
L=w+2
.
A) (w+2)*w=a
w^2+2w=a
.
B) (w+2-4)(w-2)=w^2+2w-74
(w-2)(w-2)=w^2+2w-74
w^2-4w+4=w^2+2w-74
-6w=-78
w=13 cm
.
C) L-4=13-2
L-4=11
L=11+4
L=15 cm
.
A) 13*15=195 cm^2
.
Answer: w=13, L=15
That was hard!
.
.
A)L*w=a
(w+5)w=a
.
B) w(w-5)=330
w^2-5w=330
w^2-5w-330=0
w=20.84 m (approx.) quadratic formula (the other answer was negative)
L=25.84 m approx
.
25.84*20.84=538.37 m area of park.
20.84*15.84=330 m area of flower border.
538.37-330=208.37 m^2 area of lawn. Ans.
.
Ed