For numbers 15-17, we need to remember that two of a triangle's angles are always acute and the third angle will allow us to classify the triangle based on its angles. now that we know this, let's look at #15. the first two angles listed are acute, and the third is an obtuse angle, therefore it is an obtuse triangle. on #16 we have three acute angles, so it is an acute triangle. #17 has two acute angles and a right angle so it is a right triangle.
on numbers 21-23, we need to know that a triangle with all congruent sides is called equilateral, a triangle with two equal sides is isosceles, and a triangle with no equal sides is called scalene. #21 shows two equal sides so it is an isosceles triangle. #22 has three equal sides so it is an equilateral triangle. #23 has no equal sides so it is scalene. hope this helped! :)
Essentially, what we need to do here is prove that BE=EC, BE=CB, and.or CE=BC therefore making it isosceles. With ∠AEC=∠DEB, we know AE=DE, so EC=EB (the points go in order). Therefore, as EC=EB, BEC is isosceles (it has at least 2 equal sides).
Feel free to ask further questions!
ally’s answer is sometimes true. -6.2+5.71=-11.91 5.71+-6.2=11.91 5.72-2.84=2.99
Answer: x ≤ 950
Step-by-step explanation:
5,225.00÷5.50
= 950
Let 
denote the <em>k</em>th term of the sequence. Then
where <em>d</em> is the common difference between consecutive terms in the sequence and <em>a</em>₁ is the first term.
The sum of the first <em>n</em> terms is
From the formula for , we get
So we have 
, and 
so that 
.
Then the <em>n</em>th term in the sequence is
