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# Write five pairs of integers (a, b) such that $\dfrac{a}{b}=-3$. One such pair is (6, -2) because $\dfrac{6}{-2}=-3$.

Answer Verified
Hint: We can find pairs by keeping the value of one variable in a given equation and another variable can easily be calculated as it’s just a two-variable equation. Generally, sequential integers are to be used for our ease of understanding.

Complete step-by-step answer:
Here, we have to form such pairs using integers, be it positive or negative, such that $\dfrac{a}{b}=-3$. We can form these pairs by keeping integers on one variable sequentially or randomly, i.e.,
We can start substituting integral values in one variable, let’s say for b

$\dfrac{a}{b}=-3$

Substituting b = 1 in above equation, we get
\begin{align} &\dfrac{a}{b}=-3 \\ &\dfrac{a}{1}=-3 \\ \end{align}
On cross-multiplying above equations, we get
$a=-3$

One such pair formed by the values calculated above will be i.e., pair 1: (-3, 1).
Again, substituting sequential or random values for b in the given equation i.e., b = -3, 5, 6, 10, we get
For $b=-3$, we get
\begin{align} &\dfrac{a}{b}=-3 \\ &\dfrac{a}{-3}=-3 \\ \end{align}

On cross-multiplying above equations, we get
\begin{align} &a=\left( -3 \right)\times \left( -3 \right) \\ &a=9 \\ \end{align}

Thus, pairs formed from similar operations in a given equation, we get pair 2: (9, -3).
Similarly, for$b=5$, we get
\begin{align} &\dfrac{a}{b}=-3 \\ &\dfrac{a}{5}=-3 \\ \end{align}

On cross-multiplying above equations, we get
$a=-15$

Thus, pairs formed from similar operations in a given equation, we get pair 3: (-15, 5).
Now for $b=6$, we get
\begin{align} &\dfrac{a}{b}=-3 \\ &\dfrac{a}{6}=-3 \\ \end{align}

On cross-multiplying above equations, we get
$a=-18$

Thus, pairs formed from similar operations in a given equation, we get pair 4: (-18, 6).
Now for $b=10$, we get
\begin{align} &\dfrac{a}{b}=-3 \\ &\dfrac{a}{10}=-3 \\ \end{align}
On cross-multiplying above equations, we get
$a=-30$

Thus, pairs formed from similar operations in a given equation, we get pair 5: (-30, 10).
Hence, pairs formed using given conditionality, we get (-3 ,1); (9, -3); (-15, 5); (-18, 6); (-30, 10).

Note: Student might perform a mistake in the sign conventions while substituting values of either a or b in given equation like, $\dfrac{6}{-2}=\dfrac{-6}{2}=-3$, hence pairs so formed could change from (6, -2) to (-6, 2), unknowingly.
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