Answer:
Step-by-step explanation:
The two triangles are similar and therefore we can set up a proportion
9/(9 + 72) = (3x - 20)/(3x - 20 + 56) Combine like terms on the right
9/(81) = (3x - 20)/(3x + 36) Cross multiply
9(3x + 36) = 81 (3x - 20) Remove the brackets.
27x + 324 +1620 = 243x Add 1620 to both sides
27x + 324 + 1620 = 243x Subtract 27x from both
1944 = 216x divide both sides by 216
x = 9
If you feel comfortable canceling the size of the numbers can be reduced.
9/81 = 1/9
1/9 = (3x - 20)/(3x + 36)
3x + 36 = 9(3x - 20)
3x + 36 = 27x - 180
36 + 180 = 24x
216 = 24x
216/24 = x
x = 9
There is another cancelation possible, but this is simple enough.
Answer:
B
Step-by-step explanation:
If the point lies on the circle, the distance of the point to the center would be equivalent to the circle's radius since radius is defined as the distance from the center to any point of the circle.
Since length of a radius is half of a diameter,
radius= diameter ÷2
radius= 12 ÷2
radius= 6 units
Let's find the length between each points to see which is equal to 6 units, using the distance formula below.

A. Distance between 2 points

(to 5 s.f.)
Since the distance is greater than 6 units, point A lies outside the circle.
B. Distance between 2 points

Since the distance of B from the center is 6 units, point B lies on Circle O.
Let's check the other 2 points:
C. Distance between 2 points

Since the distance of point C from the center is greater than 6 units, point C lies outside the circle.
D. Distance between 2 points

(to 5 s.f.)
Point D also lies outside Circle O.
Answer:
8
Step-by-step explanation:
check this out!
-5(a+3)=- 55
-5a-15=- 55
-5a= -55+15
-5a= -40
-5a/-5 =-40/-5
a=8
Sinx is the opposite side over the hypotenuse. The opposite side depicted here is 5, while the hypotenuse is 13.
Therefore, the answer is 5/13, or B.