<u><em>Answer:</em></u>
{x | x = 0.5 or x = 4.5}
<u><em>Explanation:</em></u>
<u>Before we begin, remember that:</u>
The modulus gives the positive value of what's inside it.
<u>This means that:</u>
|a| = |-a| = a
<u>Now, for the given, we have:</u>
|2x-5| = 4
<u>From the above rule, we can deduce that:</u>
<u>either:</u>
2x - 5 = 4
2x = 4 + 5 = 9
x = 4.5 ............> first solution
<u>Or:</u>
2x - 5 = -4
2x = 5-4 = 1
x = 0.5 ..........> second solution
<u>Now, we check:</u>
<u>at x = 4.5</u>: |2(4.5)-5| = |9-5| = |4| = 4 ..........> first solution verified
<u>at x = 0.5</u>: |2(0.5)-5| = |1-5| = |-4| = 4 .........> second solution verified
Hope this helps :)
2 equations: the first one is the sum of 2 unknown numbers x and y: x + y = 72. Now the difference is 25, so x - y = 25. Solve the first equation for y: y = 72 - x. Sub that into the second equation to solve for x: x - (72 - x) = 25. x - 72 + x = 25 and 2x - 72 = 25. Therefore, 2x = 97 and x = 48.5 That's the larger of the 2 numbers; since we subtracted y from x we defined x as the larger of the 2. Just for fun, plug x in to find that y = 23.5
