Jumlah panjang dan lebar suatu persegi panjang adalah 32cm. sedangkan luasnya adalah 240cm. tentukan (a) panjang dan lebarnya (b) kelilingnya dan (c) panjang diagonal persegi panjang

P and L : 12 and 20 cm

Perimeter : 64 cm

Diagonal = 4√34

The playground is a rectangular shape. There are several properties possessed by rectangular shapes, namely:  

•1. each angle is equal and is a right angle  

•2. the diagonals intersect and divide each other equally  

•3. sides facing the same length  

There are two rectangular shapes namely square and rectangle  

Square if all sides are the same length  

The formula used in rectangular is:  

•1.Area  

Rectangle  

w = width  

l = length  

Square  

a = length of side  

•2. perimeter  

Rectangle  

w = width  

l = length  

Square  

a = length of side  

P+L = 32 cm

Area = 240 cm²

Then

P = 32-L

Area = (32-L) x L

Area =32L-L²

240 = 32L-L²

-L²+32L-240=0

L²-32L+240 = 0

(L-12)(L-20)=0

L = 12 or L = 20

Then =P= 20 or 12

B)Perimeter= 2 x (P +L) = 2 x (12+20) = 64 cm

C) Diagonal

Phytagoras :

The ratio of the perimeters  

link  

The coordinates of the vertices of a rectangle  

link  

Solve the equation for w  

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step-by-step :

let x and 400 - x be the two numbers.  

==> 0.80x + 0.85(400 - x) = 400 - 68 from the statement of the problem.  

< ==> 0.80x + 0.85(400 - x) = 400 - 68  

==> 340 - 0.05x = 332  

< ==> -0.05x = -8 ==> x = 160, the first number ==> 400 - x = 240, the second number.