Question

the diagonals of a rectangle enclose an angle of measure 78 degree .if the perimeter of the rectangle is 36cm what is its area

Answer 1

Answer:

to take out the perimeter first we take the Lenght and breadth

formula of area of rectangle = l x b

we have to find wich number makes with muliply other number

so 18 x 2 = 36

now we have lenght and breadth

so formuka of rectangle peri = 2x l +b

2 x 18 +2 = 20

20 into 2 = 40 cm

hope it helps

Answer 2

Answer:

Step by Step Explanation

Let L & B denote the length & the breadth of the given rectangle respectively.

Hence from above data we get following relations,

L + B = 36/2 = 18

or L = 18 - B

L/B = tan (180° - 78°)/2

or (18 - B)/B = tan 51°

or B = 18/[1 + (tan 51°)] = 8.054 (cm)

Therefore,

the required area of the given rectangle

= L*B

= (18 - B)*B

= (18 - 8.054)*8.054 = 80.105 (cm^2) [Ans]

Step-by-step explanation: