Powers and Roots Practice Test 4

Let the two numbers be x and y.
Difference between the two numbers $=\mathit{x}-\mathit{y}=3$
Difference between their squares $={\mathit{x}}^2-{\mathit{y}}^2=39$
Now, ${\mathit{x}}^2-{\mathit{y}}^2=39$
$\left(\mathit{x}-\mathit{y}\right)\left(\mathit{x}+\mathit{y}\right)=39$
$3\left(\mathit{x}+\mathit{y}\right)=39$
$\mathit{x}+\mathit{y}=13$
Now from x + y = 13 and x - y = 3 we get.
Value of x = 8 and y = 5
So, the large number is x = 8