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B.InOut133171066co38Rule:

User Einnocent
by
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1 Answer

3 votes

Suppose that the rule is of the form


y=mx+b

Where m is the slope and b is the intercept

The slope can be found using the formula


m=(y_2-y_1)/(x_2-x_1)

You can take any two consecutive x and y values from the given table.


(17-3)/(3-1)=(14)/(2)=7

Similarly,


(66-17)/(10-3)=(49)/(7)=7

As you can see, you will end up with the same slope.

Now let us find the intercept b.

Take any x, y coordinates from the table


(x,y)=(1,3)

Now substitute them in the slope-intercept equation.


\begin{gathered} y=7x+b \\ 3=7(1)+b \\ 3=7+b \\ b=-7+3 \\ b=-4 \end{gathered}

So the rule is


y=7x-4

Verification:

Let us verify whether we got the correct rule or not

Substitute the input x coordinates into the rule and check the outputs y coordinates.


\begin{gathered} y=7(1)-4=7-4=3 \\ y=7(3)-4=21-4=17 \\ y=7(10)-4=70-4=66 \\ y=7(6)-4=42-4=38 \end{gathered}

As you can see, we have got the same results therefore, the rule is correct.

User Raghav Sood
by
2.9k points