bjr
1)
4 x (2 + 9) = 4 x 11 = 44
2)
(15 - 3) x 2 = 12 x 2 =24
3)
(5 + 5) x ( 5 - 5) = 10 x 0 = 0
4)
(1 + 13) - (14 - 7) = 14 - 7 = 7