D. {3, √ 2, -√ 2}.
<span>The cubic factors- (x - 3)(x² - 2) = 0.</span>
The inequality is t < 55
<em><u>Solution</u></em><em><u>:</u></em>
Given that, To qualify for the championship a runner must complete the race in less than 55 minutes
Let "t" represent the time in minutes of a runner who qualifies for the championship
Here it is given that the value of t is less than 55 minutes
Therefore, "t" must be less than 55, so that the runner qualifies the championship
<em><u>This is represented by inequality:</u></em>

The above inequality means, that time taken to complete the race must be less than 55 for a runner to qualify
Hence the required inequality is t < 55
Collect like terms (x + 7x) + (-1 + 4 - 3)
Simplify
Answer: 8x