Find the sum:

(–7) + (–9) + 4 + 16 ??????????????????

Dear Student

(-7) + (-9) + 4 + 16
= (-7) + (-9) + 4 + (+7) + (+9)
= (-7) + (+7) + (-9) + (+9) + 4
= 0 + 0 + 4 [(-a) + (+a) = 0]
=4

Thanks