The sum of the angles in a pentagon is 540°.
This means that each angle is 108°.
Inside you pentagon, a triangle is drawn. This triangle is isosceles, because the corners are on the points of the regular pentagon. You know that angle C is 108°.
Angles in a triangle add up to 180°.
B and D will be the same size as this is isosceles.
180°-108° = 72°
This is B and D. You only need one of these, so you divide by 2.
The answer is 36°.
Hope this helps :)
Answer:
(y - 2)²
Step-by-step explanation:
9y² - 12y + 4 ← is a perfect square of the form
(ax - b)² = a²x² - 2abx + b²
Compare like terms with 9y² - 12y + 4, thus
a² = 9 ⇒ a = 3
b² = 4 ⇒ b = 2 and
- 2ab = - 2 × 3 × 2 = - 12
Thus
9y² - 12y + 4 = (3y - 2)²
Answer: 3 or the whole backyard
Step-by-step explanation: In a hour she can rack 3 backyard. The question asked that how much of a backyard can she rake in 1 hour. She can rake the whole backyard in a hour.
Remember distributive property
a(b+c)=ab+ac
we can ervers it
6(31)+6(4)-6(15)=6(31)+6(4)+6(-15)=6(31+4-15)=6(20)=120