Calculate Angle BCD in a Quadrilateral with 48° and 119° Given Angles
Question
Shown below is the quadrilateral ABCD.
Calculate the size of the angle ∢BCD.
Video Solution
Solution Steps
00:00Determine angle BCD
00:03The sum of angles in a quadrilateral equals 360
00:12Substitute in the relevant values according to the given data and proceed to solve for the angle
00:15Adjacent angles ad up to 180, therefore angle B equals 90
00:33Isolate angle C
00:45This is the solution
Step-by-Step Solution
To solve this problem, follow these steps:
Step 1: Identify all given angles and understand the setup.
Step 2: Apply the sum of angles in a quadrilateral formula.
Step 3: Calculate the unknown angle.
Now, let's solve: Step 1: The problem states:
∠DAB=48∘
∠ADC=119∘
∠ABC=90∘ since it's marked as a right angle.
Step 2: Use the sum of angles in quadrilateral ABCD: ∠DAB+∠ABC+∠BCD+∠ADC=360∘ Substituting the known values: 48∘+90∘+∠BCD+119∘=360∘ Step 3: Simplify and solve for ∠BCD: 157∘+∠BCD=360∘∠BCD=360∘−157∘=203∘ Therefore, the measure of ∠BCD is 103∘.