Question

Which equation has the correct sign on the product?

A. (-9)(-9) = -81
B. (-12)(4) = 48
C. (31)(-10) = -310
D. (26)(3) = -78

Answer 1

C. (31)(-10) = -310

Explanation:

This equation has the correct sign, because multiplying a positive number and negative number gives you a negative number.

The other answer choices have the wrong signs.

Multiplying 2 negatives together gives a positive, so A is wrong.

Multiplying a negative by a positive gives a negative, so B is wrong as well.

D is wrong because multiplying 2 positive numbers gives a positive number.

So, C is correct.

Answer 2

C. (31)(-10) = -310

Explanation:

A. (-9)(-9) = -81

negative times a negative is a positive incorrect sign

B. (-12)(4) = 48

negative times a positive is a negative incorrect sign

C. (31)(-10) = -310

positive times a negative is a negative correct sign

D. (26)(3) = -78

positive times a positive is a positive incorrect sign