On a trip to the movies a family spent $35 on tickets, and another $25 on popcorn. they also spent $10 on drinks. the oldest son spent some money on candy. altogether the family spent $76. how much did the oldest son spend on candy?

Let's let the variable x represent the unknown amount that the oldest son spent on candy.

First we'll add up all our costs, and then set the equation equal to 76, because the total was $76.

x (candy) + 35 (tickets) + 25 (popcorn) + 10 (drinks) = 76 (total)

Now let's simplify this, by adding together our known prices.

35 + 25 + 10 = 70.

So now we've got the equation x + 70 = 76.
Now we just solve for x in this simple one-step equation.

x + 70 = 76

All you do is subtract 70 from both sides to get rid of the '+ 70'

x + 70 = 76
    - 70   -70

x = 6.

And that's our solution. This means that the oldest son spent $6 on candy.
We can check this by substituting our solution back into our equation.
We do this by replacing any variable x with our solution, 6.

x + 70 = 76
(6) + 70 = 76
76 = 76

Seem right? Yep!

The oldest son spent $6 on candy, final answer.

Hope this helps!!
Let me know if you need any help understanding anything and I'll try to explain as best I can.