I need help asap on number nine. it would be much appreciated. only number 9

18

Step-by-step explanation:

they are vertical angles so they are equal

6y+40=10y-32

6y+40+32=10y-32+32

6y+72=10y

6y-6y+72=10y-6y

72=4y

72/4=4y/4

18=y

-8-10

Step-by-step explanation:

Verify each case

case a) we have

-8-10

rewrite

-8-10=(-8)+(-10)

Remember that

(+1)(-1)=-1

therefore

This problem could be rewritten as an addition of two integers with the same sign

-8 and -10

case b) we have

-8+10

This is an addition of two integers with different sign

therefore

This problem could not be rewritten as an addition of two integers with the same sign

case c) we have

8-10

rewrite

8-10=(8)+(-10)

Remember that

(+1)(-1)=-1

therefore

This problem could not be rewritten as an addition of two integers with the same sign

case d) we have

-8-(-8)

rewrite

-8-(-8)=(-8)+(8)

Remember that

(-1)(-1)=+1

therefore

This problem could not be rewritten as an addition of two integers with the same sign