Question

Simplify:

(4) (–5) × (–13) + (–5) × 10

Answer 1

(–5) × (–13) + (–5) × 10
Let us first perform the multiplication.
The magnitude of (–5) is 5.
The magnitude of (–13) is 13.
The product of the magnitudes is 65.
Since the product of two negative integers is always positive, the result of the multiplication will be 65.
The expression reduces to
65 + (–5) × 10
Again, we will perform multiplication.
The magnitude of (–5) is 5.
So, the magnitude of the product is 50.
Since the product of a negative and a positive integer is always negative, the result of the multiplication is (–50).
The expression now reduces to
65 + (–50)
Ignoring the signs, let us subtract the smaller number from bigger number.
65 – 50 = 15
Since the sign of bigger number is positive, the result is 15.

∴ (–5) × (–13) + (–5) × 10 = 15