If (k, 5) lies on the line with equation 3x-y =-8, what is the value of k?

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If (k, 5) lies on the line with equation 3x-y =-8, what is the value of k?

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Answer 1 · 2017-12-04T21:07:00

$k = - 1$ $k=-1$

Explanation:

$since (k, 5) lies on the line then it satisfies the equation$ $"since "(k,5)" lies on the line then it satisfies the equation"$

$substitute into the equation and solve for k$ $"substitute into the equation and solve for k"$

$that is x = k and y = 5$ $"that is "x=k" and "y=5$

$\Rightarrow 3 k - 5 = - 8$ $rArr3k-5=-8$

$add 5 to both sides$ $"add 5 to both sides"$

$3kcancel(-5)cancel(+5)=-8+5$

$rArr3k=-3$

$"divide both sides by 3"$

$(cancel(3) k)/cancel(3)=(-3)/3$

$rArrk=-1$

Answer 2 · 2017-12-04T21:17:06

$k=-1$

Explanation:

First, you need to make the equation $3x-y=-8$ to the form $y=mx+b$

$3x-y=-8$

$-y=-8-3x$
$y=(-8-3x)/-1$
$y=8+3x$

Now, there are multiple ways you could solve this:

First way is to plug in 5 as the y value in this equation and solve for x.
$y=8+3x$
$5=8+3x$
$-3=3x$
$-1=x$

Second way is to graph this and find out.
The graph should look like this:

graph{8+3x [-10, 10, -5, 5]}
Im portant things ot remember: 8 is the y-intercept with the slope $3/1$

We see that when y=5, the slope intersects at the point (-1,5).

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If (k, 5) lies on the line with equation 3x-y =-8, what is the value of k?

Show work and explain please

2 Answers

Explanation:

Explanation:

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