Question

12- Determine o valor das seguintes expressões Numéricas:

a) 2 - [4 × (7 -12 ) - 5]

b) -2 + [(-4) × ( -7 + 12) +5]

c)13 + 2 × [-7 -5 )

d) 13 + 2 × [ -7 -5 × ( -9 + 4)]

e) -20 -5 × [(-2) × (4 -7) +8 -2 × 5

f) -20 -6 × [(-1) ×(10 -3 × 7) +8 -5 × 4 ]

♡_♡ !!

Answer 1

a) 2 - [(-4) x (-7 + 12) - 5]
2 - [(-4) x (-5) - 5]
2 -[-20 -5]
2 + 25 = 27

b) -2 + [(-4) × ( -7 + 12) +5]
-2 + [(-4) x 5 + 5]
-2 + (-20) + 5
-2 -20 +5
-22 + 5 = - 17

c)13 + 2 × [-7 -5 ) 
13 + 2 x(-12)
13-24 = -11

d) 13 + 2 × [ -7 -5 × ( -9 + 4)]
13 + 2 x [ - 7 - 5 x (-5)]
13 +2 x [-7 + 25]
13 + 2 x (18)
13 + 36 = 49

e) -20 -5 × [(-2) × (4 -7) +8 -2 × 5]
-20 -5 x [(-2) x (-3) +8 - 10]
- 20 - 5 x [6 - 2]
- 20 - 5 x 4
- 20 - 20 = - 40

f) -20 -6 × [(-1) ×(10 -3 × 7) +8 -5 × 4 ]
-20 -6x [(-1) x (10 - 21) + 8 - 20]
-20 - 6 x [(-1) x (-11) - 12]
- 20 - 6 x (11 - 12)
-20 - 6 (-1)
-20 + 6 = -14