Answer:

Step-by-step explanation:
Please refer to the attached diagram. (Apologies if the shading or resolution is a bit off.)
So, we want to find θ.
Since we formed a right triangle, we can use right triangle ratios.
We know the measure of the adjacent side to θ and the hypotenuse.
Therefore, we will use the cosine ratio:

The adjacent side is 2 and the hypotenuse is 15. By substitution:

Now, we will take the inverse cosine of both sides. So:

Use a calculator. Hence:

The angle between the ground and the ladder is about 82.34°.
Answer:
c=-2
Step-by-step explanation:
Answer:
Given: In parallelogram ABCD, AC=BD
To prove : Parallelogram ABCD is rectangle.
Proof : in △ACB and △BDA
AC=BD ∣ Given
AB=BA ∣ Common
BC=AD ∣ Opposite sides of the parallelogram ABCD
△ACB ≅△BDA∣SSS Rule
∴∠ABC=∠BAD...(1) CPCT
Again AD ∥ ∣ Opposite sides of parallelogram ABCD
AD ∥BC and the traversal AB intersects them.
∴∠BAD+∠ABC=180∘ ...(2) _ Sum of consecutive interior angles on the same side of the transversal is
180∘
From (1) and (2) ,
∠BAD=∠ABC=90∘
∴∠A=90∘ and ∠C=90∘
Parallelogram ABCD is a rectangle.
Answer:
7. x=19 2x=38
8.x=23 3x=69
9.x=12 (50-2)/4=12
10.x=15 (31-1)/2
11.x=16 (84-4)/5
12.x=27 (55-1)/2
Step-by-step explanation:
if 2 angles are opposite, it's the same
10/3 is the answer
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