Answer:
Step-by-step explanation:
Infinite solution
Answer:
Step-by-step explanation:
Trapezoid ABCD is isosceles trapezoid, because AB = CD (given). In isosceles trapezoid, angles adjacent to the bases are congruent, then
Since BK ⊥ AD, the triangle ABK is right triangle. In this triangle, AB = 8, AK = 4. Note that the hypotenuse AB is twice the leg AK:
If in the right triangle the hypotenuse is twice the leg, then the angle opposite to this leg is 30°, so,
Since BK ⊥ AD, then BK ⊥ BC and
Thus,
Now,
The explicit formula of the sequence is given by a_n = -4n(n-1).
We have to find the first five terms of the sequence.
The first term:
The second term:
The third sum:
The fourth term:
The fifth term:
Thus, option D is correct.
Answer:
40°, 80°, 120°, 120°
Step-by-step explanation:
sum the parts of the ratio, 1 + 2 + 3 + 3 = 9 parts
The sum of the interior angles of a quadrilateral is 360°
Divide this by 9 to find the value of one part of the ratio.
360° ÷ 9 = 40° ← value of 1 part of the ratio
Then
2 parts = 2 × 40° = 80°
3 parts = 3 × 40° = 120°
The 4 angles are 40°, 80°, 120°, 120°