Step-by-step explanation:
So we have...
[tex] {(x + 6)}^{2} - {x}^{2} = 144[/tex]
Expand and rearrange:
[tex] {x}^{2} + 12x + 36 - {x}^{2} - 144 = 0[/tex]
Simplify:
[tex]12x + 36 = 144[/tex]
Subtract 36 from each side:
[tex]12x =108[/tex]
Divide both sides by 12:
[tex]x = 9[/tex]
9 is the First Number
And so we can conclude that:
[tex]x + 6 = 15[/tex]
15 is the Second Number
Hope this helps!!