Keith bought 8 new baseball trading cards to add to his collection. The next day his dog ate half of his collection. There are now only 30 cards left. How many cards did Keith start with? please help!!!

52 cards

Step-by-step explanation:

call the amount he started with " x "

then he bought 8 cards

so the new equation is

x+8

then he lost half of his cards

so now the equation is

(x + 8 )/2

that amount to 30 cards as per what is given in the problem

so now the equation is

( x + 8 )/2 = 30

solve using inverse operations and simplifying

( x + 8 )/2 = 30  

         *2    *2

x + 8 = 60

   -8     -8

x = 52