Me with these i don’t understand!

First exercise:

Let's call the initial weight of the dog . We know that after the first year the difference is -1.56 pound, so the weight after one year is

After another year, the new weight is But we know the way to express in terms of , so we have

Second exercise:

You need an equation to be satisfied when . Actually, this is already an equation, so we can simply rearrange it to get , which is an equation with solution 26.

Third exercise:

Rearrange the left hand side to get

Since 8 appears in both sides, we can simplify it:

Add 0.3 to both sides:

there are 25 people coming to the party

step-by-step explanation:

the text says that there will be 22 children at this party, 1 teacher, and 2 parents. so if you add them all together (22+1+2) it will equal 25. (=25)

what is the question