How did my book go from: 4 5 = x 30 to 4 1 = x 6 I understand that I could have cross multiplied it in the first place but what I don't understand is why my book changes the denominators without changing the numerators when simplifying the problem.

Question

How did my book go from:        4    5    =      x    30   to       4    1    =      x    6  I understand that I could have cross multiplied it in the first place but what I don&#039;t understand is why my book changes the denominators without changing the numerators when simplifying the problem.

Krish Finley · Accepted Answer

You can rewrite 30 as   5  ×  6      4    5    =      x          5      ×      6             multiply both sides by 5       5  ×      4    5    =  5  ×      x          5      ×      6      if you then do some rearrangement you can get:      5    5    ×      4    1    =      5    5    ×      x    6  Then replacing 5/5 with 1 gives your result:      4    1    =      x    6

How did my book go from: 4 5 </mfrac> = x 30 </mfrac> to 4

Answered question

Answer & Explanation

New Questions in Pre-Algebra