Lewis and his sister both open savings accounts. Each begin with a balance of zero dollars. For every 4 dollars that Lewis saves in his account, his sister saves 9 dollars. If Lewis has 64 dollars in his account, how much money does his sister have?

144 dollars

Step-by-step explanation:

We are told that:

Lewis and his sister both begin with a balance of zero dollars.

Now, for every 4 dollars that Lewis saves in his account, his sister saves 9 dollar.

Now, if Lewis has 64 dollars in his account, it means he saved 4 dollars for 64/4 times or 16 times.

Therefore his sister saved 9 dollars for 16 times too.

Thus, his sister saved: 16 × 9 = 144 dollars

-2x + 7 = 7

subtract 7 from both sides.

-2x = 0

divide both sides by -2.

x = 0

if you are looking for the unit rate then the answer would be 9 because unit rate is distance divided by time.

step-by-step explanation: