Answer:
61=x ( vertical opposite angle)
61=y (corresponding angle)
First we find the measurement of dark dot .
ANd for that we have to use the formula of the angle formed by the intersection of chord .
Let the dark dot be t.
So we have

t and z are linear pair and sum of angles of linear pair =180 degree.
So we get

Solution: The commutative property of addition states that when two numbers are being added, their order can be changed without affecting the sum.
2(21x − 7) + 4(3x + 2) = 6(2x + 9) + 3
42x - 14 + 12x + 8= 12x + 54 + 3
54x - 6= 12x + 57
54x=12x + 63
42x=63
x= 63/42
x= 3/2
Answer:
-3+(-6) = -9
Step-by-step explanation:
a negative 3 plus another negative 6 is a negative 9. Is just like if you borrow $3 from your friend and borrow $9 from another friend. That means you own two of your friends a total of $9. This can be mathematically illustrate as: -3 + (-6)= -9