Both claims are false. In fact, $a$ and $\frac{1}{a}$ are one the multiplicative inverse of the other. This means, by definition of multiplicative inverse, that

$a \cdot \dfrac{1}{a} = 1 \quad\forall a \in \mathbb{R}$

So, it doesn't matter if $a$ is positive or negative: the multiplication of one number and its inverse will always be 1: for example,

$(-2) \cdot \dfrac{1}{-2} = \dfrac{-2}{-2} = 1$

Similarly, when you multiply two number, the sign of the product depends on the sign of the factors as follows:

$(+) \cdot (+) = (+)$
$(+) \cdot (-) = (-)$
$(-) \cdot (+) = (-)$
$(-) \cdot (-) = (+)$

So, the multiplication of two negative numbers is a positive number.

8 0

3 years ago

The cost to print digital photos at a local store is

snow_tiger [21]

<h2>The cost is same for both the options if we purchase 27 photos</h2>

Step-by-step explanation:

Cost of a photo at a local store is $0.25 per photo. This cost can be modeled to be linear in number of photos as $C_{1}(x)=0.25x$ .

Cost of photos purchased online is $0.15 per photo. However there is a shipping cost of $2.70. This can also be modeled to be linear in number of photos as $C_{2}(x)=2.70+0.15x$ .