Question

Which expression is equivalent to 2/7k(k-7)? Assume k=0.A. 2/7-k,B. 2/7-2/k,C. 2k/7-7,D. 2k/7k-2k

Answer 1

$\dfrac{2}{7k}(k-7)\qquad|\text{use distributive property}\\\\=\left(\dfrac{2}{7k}\right)(k)-\left(\dfrac{2}{7k}\right)(7)=\dfrac{2}{7}-\dfrac{2}{k}$

Answer 2

ANSWER

B.
$\frac{2}{7k} (k - 7) = \frac{2}{7}- \frac{2}{k}$



EXPLANATION

The given expression is

$\frac{2}{7k} (k - 7)$
where k≠0

We expand the bracket to get,


$\frac{2}{7k} (k - 7) = \frac{2}{7k} \times k - \frac{2}{7k} \times 7$



We now cancel out the common factors to obtain,


$\frac{2}{7k} (k - 7) = \frac{2}{7} \times 1- \frac{2}{k} \times 1$



We now simplify to obtain,

$\frac{2}{7k} (k - 7) = \frac{2}{7}- \frac{2}{k}$


The correct answer is option B.