Advertisements
Advertisements
Question
A quadrilateral has three acute angles each measures 80°. What is the measure of the fourth angle?
Advertisements
Solution
\[\text{ Let x be the fourth angle } . \]
\[ \text{ Since, the sum of all angles of a quadrilateral is } 360°, \text{ we have: } \]
\[80° + 80° + 80° + x = 360° \]
\[ \Rightarrow 240° + x = 360° \]
\[ \Rightarrow x = 120° \]
\[ \therefore \text{ The fourth angle is } 120° .\]
APPEARS IN
RELATED QUESTIONS
What is the sum of the measures of the angels of a convex quadrilateral? Will this property hold if the quadrilateral is not convex? (Make a non-convex quadrilateral and try!)
Three angles of a quadrilateral are equal. Fourth angle is of measure 150°. What is the measure of equal angles.
Use the following figure to find the value of x
In an isosceles trapezium one pair of opposite sides are _____ to each Other and the other pair of opposite sides are _____ to each other.
Two opposite angles of a parallelogram are 100° each. Find each of the other two opposite angles.
In a parallelogram ABCD, its diagonals AC and BD intersect each other at point O.
If AC = 12 cm and BD = 9 cm ; find; lengths of OA and OD.
If bisectors of ∠A and ∠B of a quadrilateral ABCD intersect each other at P, of ∠B and ∠C at Q, of ∠C and ∠D at R and of ∠D and ∠A at S, then PQRS is a ______.
The common part between the two angles BAC and DAB in the following figure is ______.
Using the information given, name the right angles in part of figure:
BA ⊥ BD
Draw a rough sketch of a quadrilateral PQRS. Draw its diagonals. Name them. Is the meeting point of the diagonals in the interior or exterior of the quadrilateral?
