Find the value of x. #9,10,11,&12
1 answer:
Answer:
Step-by-step explanation:
9). It's given in the triangle → Two angles are equal in measure
Therefore, by the definition of an isosceles triangle, opposite sides of the equal angles are equal in measure.
x = 12
10). Two sides of the given triangles are equal in length.
By the definition of an isosceles triangle, opposite angles of the equal sides of the triangle will be equal in measure.
Therefore, y = 55°
By the triangle sum theorem,
x° + y° + 55° = 180°
x° + 55° + 55° = 180°
x = 180 - 110
x = 70°
11). By the definition of an isosceles triangle, opposite sides of the equal angles will be equal in measure.
x + 3 = 12
x = 9
12). By the definition of an isosceles triangle, opposite angles of the equal sides of the triangle will be equal in measure.
m∠2 = 53°
x + 65 = 53
x = 53 - 65
x = -12
You might be interested in
Question not well presented and diagram is missing
Quadrilateral WILD is inscribed in circle O.
WI is a diameter of circle O.
What is the measure of angle D?
See attached for diagram
Answer:
Step-by-step explanation:
Summation of opposite angles of a quadrilateral inscribed in a circle is 180°, given that the vertices are on the circle.
Given
<WIL = 45°
<ILD = 109°
In the attached;
<WIL + <WDL = 180° (Opposite angle of quadrilateral)
Substitute 45° for <WIL in the above expression
45° + <WDL = 180° ---- Collect like terms
<WDL = 180° - 45°
<WDL = 135°
Hence, the measure of angle D is 135° (See attached)
