A regular pentagon ABCDE is shown Work out the size of X

Mathematics

2 answers:

nikdorinn [45]2 years ago

7 0

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 :)

Goshia [24]2 years ago

4 0

Answer:

X = 36°

Step-by-step explanation:

ABCDE regular pentagon => C = 108°

x = A = (180° - 108) : 2 = 72 : 2 = 36 °

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The population of California is approximately 38,040,000. The population of Texas is about 2.606 × 107. What is the approximate

liubo4ka [24]

Answer:

The total population of these two states is:

$3.804\times \:\:10^7+2.606\times \:\:10^7\:=10^7\times \:\:6.41$

Therefore, option C is correct.

Step-by-step explanation:

The population of California is approximately 38,040,000.

The population of Texas is about 2.606 × 10⁷.

Writing the population of California i.e.38,040,000 in scientific notation by moving the decimal point 7 places to the left and dropping the 0's on the right side as they're after the decimal point now.

i.e.

38,040,000 = 3.804 x 10⁷

So adding 3.804 x 10⁷ and 2.606 × 10⁷

i.e.

$3.804\times \:10^7+2.606\times \:10^7$