Arithmetic · real student question

Evaluate 4 - 3 - (-2) - [12 - 3 + 4].

Question

Evaluate

43(2)[123+4].4-3-(-2)-\left[12-3+4\right].

Step-by-step solution

  1. Evaluate the bracket first. Brackets outrank every other operation, and inside them addition and subtraction run left to right:

    123+4=9+4=13.12-3+4=9+4=13.

    A common slip is to treat 3+4-3+4 as a unit and compute 127=512-7=5; addition and subtraction have equal precedence, so the left-to-right order is what decides.

  2. Rewrite the expression with the bracket replaced. Substituting 1313 and keeping the minus sign that was in front of it:

    43(2)13.4-3-(-2)-13.

    The square brackets are only grouping symbols here — they carry no multiplication, so no distribution is involved.

  3. Convert the double negative. Subtracting a negative number is the same as adding its magnitude:

    (2)=+2,-(-2)=+2,

    so the expression becomes

    43+213.4-3+2-13.

    Parentheses around 2-2 exist purely to separate the two signs; they do not change the value of the number.

  4. Add and subtract from left to right. One term at a time:

    43=1,1+2=3,313=10.4-3=1,\qquad 1+2=3,\qquad 3-13=-10.

    So the value of the expression is 10-10.

  5. Check by regrouping. Splitting into positives and negatives, (4+2)(3+13)=616=10(4+2)-(3+13)=6-16=-10 ✓. This regrouping is legitimate because every term keeps its own sign, and it gives an independent route to the same answer.

Answer

10-10

Need to solve a different problem like this? Open the solver →