For the expression 34- 34a to have a negative value, what must be true about the value of a ?

a>0

Step-by-step explanation:

if a is negative then the subtraction sign would switch. therefore, for the expression to have a negartive value a must be greater than 0

12r - 8 - 12

you have to combine like terms. below i have bolded the like terms:

12r - 8 - 12

together it combines to:

12r - 20

hope this !