its width.
if the representation goes like this:
Let the X- be the length and
Let the Y- be the width
please tell me the 1st and 2nd equation...
i humbly ask for your best answer.
i really need those for my MATH project.
please post your solution for i can know how.
please?? please?? puhlease??
i don't want to have failing grades...
so please kindly help me on this one.
i beg you all.... please????????????? :(
7. The perimeter of a rectangle is 250m. Find the dimensions of the rectangle if its length is 45m longer than
2008-07-31 1:27 pm
回答 (10)
2008-07-31 1:43 pm
✔ 最佳答案
Parameter = 2*length + 2*widthIf x = y+45 then parameter = 2y+2(y+45)=250
2y+(2y+90)=250
4y=160
y=40m
x=40+45
x=85m
If you don't fully understand, send me a msg.
2008-07-31 9:19 pm
Only 1 representation is sufficient to solve the problem:
Width (x):
2(x + x + 45) = 250
x + x + 45 = 125
2x = 80
x = 40
Length:
= 40 + 45
= 85
Answer: 40 by 85 meters is the dimension.
Proof (perimeter is 250 meters):
= 2(40 meters) + 2(85 meters)
= 80 meters + 170 meters
= 250 meters
Width (x):
2(x + x + 45) = 250
x + x + 45 = 125
2x = 80
x = 40
Length:
= 40 + 45
= 85
Answer: 40 by 85 meters is the dimension.
Proof (perimeter is 250 meters):
= 2(40 meters) + 2(85 meters)
= 80 meters + 170 meters
= 250 meters
2008-07-31 8:36 pm
perimeter of rectangle is
2X + 2Y = 250 --> this will be equation 1
but X = Y + 45 --> this is equation 2
just substitute eq 1 to eq 2
2(Y + 45) + 2Y = 250
2Y + 90 +2Y = 250
4Y = 160
Y = 40
thwn substitute back to equation 2 the value of Y
X = 40+45
X = 85
therefore, the length is 85 and the width is 40
2X + 2Y = 250 --> this will be equation 1
but X = Y + 45 --> this is equation 2
just substitute eq 1 to eq 2
2(Y + 45) + 2Y = 250
2Y + 90 +2Y = 250
4Y = 160
Y = 40
thwn substitute back to equation 2 the value of Y
X = 40+45
X = 85
therefore, the length is 85 and the width is 40
2008-07-31 10:37 pm
2(x + y) = 250 (solve by using substitution)
x - 45 = y
2(x + y) = 250
x + (x - 45) = 250/2
x + x - 45 = 125
2x = 125 + 45
2x = 170
x = 170/2
x = 85
x - 45 = y
85 - 45 = y
y = 40
â´ x (length) = 85 (m) , y (width) = 40 (m)
(the dimensions are 85 by 40.)
x - 45 = y
2(x + y) = 250
x + (x - 45) = 250/2
x + x - 45 = 125
2x = 125 + 45
2x = 170
x = 170/2
x = 85
x - 45 = y
85 - 45 = y
y = 40
â´ x (length) = 85 (m) , y (width) = 40 (m)
(the dimensions are 85 by 40.)
2008-07-31 9:34 pm
Length = L
Breadth = B
L = B + 45
2L + 2B = 250
2B + 90 + 2B = 250
4B = 160
B = 40 m
L = 85 m
Breadth = B
L = B + 45
2L + 2B = 250
2B + 90 + 2B = 250
4B = 160
B = 40 m
L = 85 m
2008-07-31 8:51 pm
Length = (y +45)
Width = y
2(width) + 2(Length) = Perimeter
So: 2(y +45) + 2(y) = 250
4y +90 = 250
4y = 160
y = 40
So:
Length = (y +45) = (40 +45) = 95
Width = 40
Width = y
2(width) + 2(Length) = Perimeter
So: 2(y +45) + 2(y) = 250
4y +90 = 250
4y = 160
y = 40
So:
Length = (y +45) = (40 +45) = 95
Width = 40
2008-07-31 8:42 pm
You've been asking stuff for your "math project"... Now didn't you learn at least one thing in your math class? Anyway...
x - length
y - width
x - y+45
Perimeter = 2(l+w)
4y+90 = 250
4y = 160
y = 40
Width = 40m
Length = 85m
x - length
y - width
x - y+45
Perimeter = 2(l+w)
4y+90 = 250
4y = 160
y = 40
Width = 40m
Length = 85m
2008-07-31 8:42 pm
Perimeter=length+lenght+width+width (in general)
Perimeter=(width+45)X2+2X(width) ( your case)
Perimeter=2Xwidth+90+2Xwidth=250
250=4Xwidth+90 .Then 160=4Xwidth,so width is 40 meters,
and lenght is 40+45=85 meters.
CHECK:40+85+40+85=250.
Perimeter=(width+45)X2+2X(width) ( your case)
Perimeter=2Xwidth+90+2Xwidth=250
250=4Xwidth+90 .Then 160=4Xwidth,so width is 40 meters,
and lenght is 40+45=85 meters.
CHECK:40+85+40+85=250.
2008-07-31 8:42 pm
ok so P=perimeter= 250
250=2X+2Y
X=45+Y NOW you substitude the second equation in the fisrt once and it will be :
250=2(45+Y)+2Y
250=90+2Y+2Y
250=90+4Y
250-90=4Y
160=4Y
160/4=Y
Y=40 sooo width is 40cm
and since lenght is 45 cm longer
X=Y+45=40+45=85 cm
check:P=2*85 +2* 40=170+80=250cm CORRECT :)
250=2X+2Y
X=45+Y NOW you substitude the second equation in the fisrt once and it will be :
250=2(45+Y)+2Y
250=90+2Y+2Y
250=90+4Y
250-90=4Y
160=4Y
160/4=Y
Y=40 sooo width is 40cm
and since lenght is 45 cm longer
X=Y+45=40+45=85 cm
check:P=2*85 +2* 40=170+80=250cm CORRECT :)
2008-07-31 8:38 pm
let
breadth = x
length = x + 45
so
perimeter = 2(l + b)
250 = 2( x + x + 45)
250 = 4x + 90
4x = 250 - 90
4x = 160
x = 40
length = x + 45 = 40 + 45 =85 m
breadth = x = 40 m
breadth = x
length = x + 45
so
perimeter = 2(l + b)
250 = 2( x + x + 45)
250 = 4x + 90
4x = 250 - 90
4x = 160
x = 40
length = x + 45 = 40 + 45 =85 m
breadth = x = 40 m
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