Answer: ∠ECB = 60°
Step-by-step explanation:
First, find the value of <em>x </em>by adding them up.
x + 3x + 2x = 6x
Since we know that all of the angles create a 180° angle, we can set up a proportion.
6x = 180°
To find the value of x, divide both sides by 6.
6x ÷ 6 = x
180 ÷ 6 = 30
So now the proportion is x = 30.
Now that we now x = 30, we can plug in 30 to the angle measures.
∠DCA = 30°
∠DCE = 90°
∠ECB = 60°
So angle ECB is 60°.
hope this helps!
Well the average would change from 85 to 85.4
Answer:
see explanation
Step-by-step explanation:
Using the trigonometric identity
sin²x + cos²x = 1 ⇒ sin²x = 1 - cos²x
Given
sin²x + 7cosx + 17
=1 - cos²x + 7cosx + 17
= - cos²x + 7cosx + 18 ← factor out - 1 from each term
= - (cos²x - 7cosx - 18)
Consider the factors of the constant term (- 18) which sum to give the coefficient of the cosx term (- 7)
The factors are - 9 and + 2, thus
= - (cosx - 9)(cosx + 2) ← in factored form
Answer:
D..... 3 lines of Symmetry
670,130,000 Km or 416,399,477 Miles apart
