Bytelearn - cat image with glassesAI tutor

Welcome to Bytelearn!

Let’s check out your problem:

If 2x78 |2x-7| \leq 8 , what is the greatest possible value of x7 |x-7| ?\newline(A) 12-\frac{1}{2}\newline(B) 00\newline(C) 12\frac{1}{2}\newline(D) 152\frac{15}{2}

Full solution

Q. If 2x78 |2x-7| \leq 8 , what is the greatest possible value of x7 |x-7| ?\newline(A) 12-\frac{1}{2}\newline(B) 00\newline(C) 12\frac{1}{2}\newline(D) 152\frac{15}{2}
  1. Absolute Value Definition: To solve the inequality 2x78|2x-7|\leq 8, we need to consider the definition of absolute value, which states that ab|a| \leq b implies bab-b \leq a \leq b for any real number aa and non-negative real number bb.\newlineSo, we can write the inequality as two separate inequalities:\newline82x78-8 \leq 2x-7 \leq 8
  2. Solving Left Inequality: Now, we solve the left inequality for xx:82x7-8 \leq 2x-7Add 77 to both sides:12x-1 \leq 2xDivide both sides by 22:12x-\frac{1}{2} \leq x
  3. Solving Right Inequality: Next, we solve the right inequality for xx:2x782x−7 \leq 8Add 77 to both sides:2x152x \leq 15Divide both sides by 22:x152x \leq \frac{15}{2}
  4. Combining Inequalities: Combining both inequalities, we get the solution for xx:12x152-\frac{1}{2} \leq x \leq \frac{15}{2}
  5. Finding Greatest Value: Now, we need to find the greatest possible value of x7|x-7|. To do this, we need to consider the distance of xx from 77 on the number line. The greatest distance will occur at the endpoints of the interval for xx.\newlineWe calculate x7|x-7| at both endpoints:\newlineFor x=12x = -\frac{1}{2}: x7=127=(12+142)=152=152|x-7| = \left| -\frac{1}{2}-7 \right| = \left| -\left(\frac{1}{2} + \frac{14}{2}\right) \right| = \left| -\frac{15}{2} \right| = \frac{15}{2}\newlineFor x=152x = \frac{15}{2}: x7=1527=152142=12=12|x-7| = \left| \frac{15}{2}-7 \right| = \left| \frac{15}{2}-\frac{14}{2} \right| = \left| \frac{1}{2} \right| = \frac{1}{2}
  6. Finding Greatest Value: Now, we need to find the greatest possible value of x7|x-7|. To do this, we need to consider the distance of xx from 77 on the number line. The greatest distance will occur at the endpoints of the interval for xx. We calculate x7|x-7| at both endpoints: For x=12x = -\frac{1}{2}: x7=127=(12+142)=152=152|x-7| = \left| -\frac{1}{2}-7 \right| = \left| -\left(\frac{1}{2} + \frac{14}{2}\right) \right| = \left| -\frac{15}{2} \right| = \frac{15}{2} For x=152x = \frac{15}{2}: x7=1527=152142=12=12|x-7| = \left|\frac{15}{2}-7\right| = \left|\frac{15}{2}-\frac{14}{2}\right| = \left|\frac{1}{2}\right| = \frac{1}{2} Comparing the two values, we see that 152\frac{15}{2} is greater than xx00, so the greatest possible value of x7|x-7| is 152\frac{15}{2}.

More problems from Transformations of functions