ABCD is a rhombus. Find 'x'?
1 Answer
Nov 19, 2017
Explanation:
"using the properties of the rhombus"using the properties of the rhombus
• " the diagonals bisect the angles"∙ the diagonals bisect the angles
• " the diagonals bisect each other at right angles"∙ the diagonals bisect each other at right angles
• " opposite sides are parallel"∙ opposite sides are parallel
" BD is a diagonal and bisects "angleADC BD is a diagonal and bisects ∠ADC
rArrangleADB=angleCDB=x⇒∠ADB=∠CDB=x
angleABD=angleCDB=x rarrcolor(blue)"alternate angles"∠ABD=∠CDB=x→alternate angles
"the sum of the angles in the lower triangle" =180^@the sum of the angles in the lower triangle=180∘
rArr36^@+90^@+x=180⇒36∘+90∘+x=180
rArrx=180-36-90=54^@⇒x=180−36−90=54∘