Question 94·Easy·Linear Inequalities in One or Two Variables
A robotics competition awards points for completed challenges and subtracts penalty points for rule violations. A team’s final score is .
To qualify for the next round, a team must have a final score of at least .
Which ordered pair satisfies this requirement?
When an inequality is given and the choices are ordered pairs, the fastest method is substitution: compute the left-hand side for each choice and check whether it meets the inequality. Stop as soon as you find a choice that works, then quickly verify the others do not.
Hints
Translate the condition
“At least ” translates to an inequality using .
Use substitution
For each choice, plug in the -value and -value into and compute the result.
Compare to 6
A choice works only if the computed score is or greater.
Desmos Guide
Enter the inequality
In Desmos, enter the inequality . This will shade the region of solutions.
Plot each point
Plot each answer choice as a point, for example by typing , , , and .
Identify the solution
The solution is the point that lies in the shaded region (or on the boundary if the inequality includes or ).
Step-by-step Explanation
Write the inequality
“At least ” means
Test the answer choices
Substitute each ordered pair into .
- For : , not at least .
- For : , not at least .
- For : , which is at least .
- For : , not at least .
Therefore, the ordered pair that satisfies the requirement is .