Answer:
The correct option is parallelogram ABCD is a rhombus, because the diagonal bisects two angles
Step-by-step explanation:
In triangle ABD:
∠B = ∠D
Thus AB=AC by the property of opposite sides of equal angles are equal
In triangle CBD
∠B = ∠D
Thus CB=CD by the property of opposite sides of equal angles are equal
Thus all four sides of quadrilateral ABCD are equal
And diagonal BD bisects the angles
So, it is a rhombus
Therefore the correct option is parallelogram ABCD is a rhombus, because the diagonal bisects two angles....
Answer:
-70x + 21
Step-by-step explanation:
1-8(10x-3)
-7(10x-3)
Use distributive property
-70x + 21
(This is how we learned to do it in my school)
Using sine formula we have
8/sin60 = x/sin30
hence x= 8/√3 = 4.62
Answer:
a
Step-by-step explanation:
there is an unknown thingy which is x
Consider the attached figure. If AB has length 1, then BC has length sin(15°) and CD (the altitude of triangle ABC) has length sin(15°)·cos(15°).
By the double angle formula for sin(α), ...
... sin(2α) = 2sin(α)cos(α)
Rearranging, this gives
... sin(α)·cos(α) = sin(2α)/2
We have
... CD = sin(15°)·cos(15°) = sin(2·15°)/2
... CD = sin(30°)/2 = (1/2)/2 = 1/4
That is, the altitude, CD, is 1/4 the hypotenuse, AB, of triangle ABC.
