Solving Linear Equations

If $3x + 5 = 20$, what is the value of $x$?

A chemical solution is made by mixing $2x$ liters of solution A with $3x$ liters of solution B. If the total volume is 25 liters, what is the value of $x$?

If $4x - 7 = 2x + 9$, what is the value of $x$?

A solution contains $H_{2}O$ and $NaCl$. If the mass of $H_{2}O$ is $x$ grams and the mass of $NaCl$ is $2x$ grams, and the total mass is 120 grams, what is $x$?

If $x/4 + 2 = 7$, what is the value of $x$?

A chemist has $x$ grams of a substance that decomposes into $2x$ grams over time. If the total amount after decomposition is 150 grams, what is $x$?

If $5x - 3 = 2x + 12$, what is the value of $x$?

A solution of $H_{2}SO_{4}$ has $x$ moles in a $2L$ container. If the total number of moles is 4, what is $x$?

If $2x + 3 = x + 10$, what is the value of $x$?

For a reaction, $x$ moles of $CO_{2}$ are produced for every $2x$ moles of $O_{2}$. If the total moles produced are 30, what is the value of $x$?