Answer:
8: 90 degrees, 9: 165 degrees, 6: 81 degrees, 7: angles in the same segment are equal
Step-by-step explanation:
For question 8:
Notice how the line AB just barely touches the edge of the circle. We call this kind of line a tangent. The point O is at the center of the circle so the line OB is a radius. The angle between a tangent and a radius is always 90 degrees, so ABO is 90 degrees.
For question 9:
By the exact same logic as 8, ACO is also 90 degrees. The sum of interior angles in a 4 sided shape (a quadrilateral) is always 360 degrees. This means that 15 + 90 + 90 + x = 360 = 195 + x so x = 360 - 195 = 165
For question 6/7:
We use the theorem that the angles in the same segment are equal. This means that a is 81 degrees.
Answer:
6:5
Step-by-step explanation:
Bubble algae cells can grow up to 5 cm in diameter. Calculate the surface area : volume ratio of this cell.
The algae is spherical in nature
Volume of the algae =4/3 pi r³
Volume of the algae = 4/3×pi×2.5³
Volume of the algae = 62.5/3 pi
Surface area = 4pi r²
Surface area = 4pi ×2.5²
Surface area = 25pi
Taking their ratio
surface area : volume ratio
= 25pi:62.5/3 pi
= 25 × 3/62.5
= 1.2
Hence the required ratio is 12/10 which is 6:5
Answer:
x=30
Step-by-step explanation:
you distribute the negative to 2x and 19
3x+4-2x-19=15
then you combine like terms
x-15=15
you add 15 to both sides
x=30
It would be nonsense, as if the beetle were at normal size, then it would be considered 1/1 as a scale. If you wanted to increase it, you would increase the numerator.
Answer:
y = 0.4x + 2
Step-by-step explanation: