Question

Ten times the number n decreased by 13 is equal to the square of the same number n increased by 3

Answer 1

$10n - 13 = {n}^{2} + 3$
${n}^{2} - 10n + 16 = 0$
$(n - 2) (n - 8) = 0$
n=2
check it:

10(2)-13=
${2}^{2} + 3$