One of the diagonals of a rhombus is thrice as the other. The area of the rhombus is 54 sq. Cm. The sum of the length of the diagonals.

Step-by-step explanation:

let one diagonal=x

other diagonal=3x

area=1/2 (x±3x)=3/2 x²=54

x²=54×3/2=81

x=9 cm  

3x=3×9=27

sum of diagonals=x+3x=4x=4×9=36 cm

according to the triangle sum theorem, all the angles in a triangle must add up to 180 degrees. if we know one angle is already 90, we do 180-90=90. the other 2 angles must add up to 90, exactly.

step-by-step explanation:

i think the answer would be c