Question 19·Easy·Nonlinear Equations in One Variable; Systems in Two Variables
The equation above relates the variables and . Which expression gives in terms of ?
When a question asks for one variable "in terms of" another, treat it like solving a simple linear equation: identify the variable you need to isolate (here, ), then use inverse operations to move all other terms to the opposite side, doing the same operation to both sides. Keep the entire expression together when you move it (like ) and pay close attention to signs so you don’t accidentally add when you should subtract or flip a sign incorrectly.
Hints
Focus on isolating y
You want the equation in the form . What term is currently being added to on the left side?
Undo the operation with y
Since is added to , what operation can you do to both sides of the equation to remove from the left side?
Be careful with signs
When you move to the other side, does it become a plus or a minus on the right side? Think about what subtracting that whole term from both sides looks like.
Desmos Guide
Enter the original equation
Type the original equation exactly as given: 3*(x - 2)^2 + y = 5. Desmos will graph this relation (a parabola).
Test each answer choice
For each answer option, enter a new line in Desmos with that choice (for example, y = 5 + 3*(x - 2)^2, then try the others one by one).
Compare the graphs
For the correct choice, its graph will exactly overlap the graph of the original equation for all visible -values. If the graphs do not perfectly match, that answer choice does not represent the same relationship.
Step-by-step Explanation
Understand the goal
You are given the equation
The phrase "gives in terms of " means you need to solve this equation for , so that the equation looks like .
Isolate the y-term
In the equation , the term is added to .
To get by itself on the left side, you need to undo this addition by subtracting from both sides of the equation.
After you subtract from both sides, the left side will just be , and the right side will be minus that same term.
Write the new equation and match the answer choice
Subtracting from both sides gives
The terms cancel on the left, leaving
Now look at the answer choices and select the one that matches this equation exactly: .