Question

Is the statement true or false? If false, give a counterexample.

For all real numbers a, b and c, a(b + c) = ab + bc.

A. true
B. false; a(b + c) = ab − ac
C. false; if a = b = c = 1, then 1(1 + 1) ≠ 1(1) + 1(1)
D. false; if a = 1, b = 2, and c = 3, then 1(2 + 3) ≠ 1(2) + 2(3)

Answer 1

D. false; if a = 1, b = 2, and c = 3, then 1(2 + 3) ≠ 1(2) + 2(3)

Explanation:

A is false, because the a is being distributed/ being multiplied to all terms inside the parenthesis, and not the term b.

B is also false. There is no indicated negative signs.

C is also false because 1(1 + 1) is EQUAL to 1(1) + 1(1)

D is true.