Question

Cut 63 cm stick into two pieces in such a way that the first piece is 7 less than the second one. Let x be the second one.

Answer 1

We have divided the bar into two parts. For example, x and y.

Explanation:

So, we have

63cm=x+y (1)

But one of those parts is 7 centimeters smaller than the other.We take y as the smallest part.Then:

y=x-7cm (2)

we replace this information in the first equation

63cm=x+(x-7cm)

63cm=x+x-7cm

7 goes to add to the other side

63cm+7cm=2x

70cm=2x

2 goes to divide to the other side

35cm=x

from the second equation we have

y=x-7cm

y=35cm-7cm=28cm

Finally

x=35cm

y=28cm

x+y=35cm+28cm=63cm

Answer 2

The second piece would be 28 cm.
You could solve this by subtracting 7 from 63 first. Next you divide it by two one piece is 35 and the other 28.
(Have a nice day :) )