Then the length of the smaller side of the rectangle is, in cm,
a.8
b.6
c.7
d.10
e.None of these
2006-08-05 15:18:53 · 7 answers · asked by mellissa b 1 in Education & Reference ➔ Homework Help
the rectangle would be 11cm x 7 cm....right?
the perimeter: 2(11)+2(7)=36 cm
Area: 11 x 7=77 cm
2006-08-05 15:26:20 · answer #1 · answered by sammy22005 5 · 0⤊ 0⤋
L = longer side
S = smaller side
Perimeter = 2S + 2L = 36 cm
Area = S*L = 77 cm^2
77 = S*L ----------------> S = 77 / L
2S + 2L = 36 ------------> 2*(77/L) + 2L = 36
154 / L + 2L = 36
154 + 2L^2 = 36L
2L^2 - 36L + 154 = 0
L^2 - 18L + 77 = 0
(L - 11)(L - 7) = 0
L = 11 or 7 cm
S = 77 cm / L
so, S = 77 cm^2 / 11 cm or S = 77 cm^2 / 7 cm
S = 7 cm or 11 cm
Since S is the smaller side,
S = 7 cm
L = 11 cm
Answer is "c"
2006-08-05 22:26:47 · answer #2 · answered by Anonymous · 0⤊ 0⤋
Answer:c 36-(7x2)=22
22 divided by 2=11
11 x 7=77( correct!)
2006-08-06 01:21:30 · answer #3 · answered by Echo Forest 6 · 0⤊ 0⤋
the answer is 7,the option (c) and the sides are 11 cm and 7 cm
2006-08-05 22:26:09 · answer #4 · answered by raj 7 · 0⤊ 0⤋
2W + 2L = 36
W*L = 77
2L = 36 - 2W
L = 18 - W
W*(18-W) = 77
18W-W^2 = 77
one answer is going to positive the other will be negative
obviously the positive one is the right one. solve for L and one of them will be the shorter side.
BTW chances are its either gonna be c. or e. because 7 is the only one that goes into 77 evenly
2006-08-05 22:25:56 · answer #5 · answered by Jake S 5 · 0⤊ 0⤋
c. Because the other side would be 11cm, and 7x11 gives you the area, or 77 sq cm.
2006-08-05 22:23:08 · answer #6 · answered by RepoMan18 4 · 0⤊ 0⤋
c
2006-08-05 22:22:15 · answer #7 · answered by Krusd 4 · 0⤊ 0⤋