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Is y = -6x +7 the equation for the table? How do you know? If not, write the correct equation.

Is y = -6x +7 the equation for the table? How do you know? If not, write the correct-example-1
User OtherDewi
by
6.1k points

1 Answer

1 vote

Answer:

The given equation is incorrect. The equation should be y = 4x-3

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Step-by-step explanation:

Plug any x value from the table into the equation. We should get the y values shown in the table. If not, then we have the wrong equation.

Plug in x = -1 to get

y = -6x + 7

y = -6(-1) + 7

y = 6 + 7

y = 13

We should have gotten y = -7 which is what the table indicates. Since we got a different y value, this means we have the wrong equation.

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To find the correct equation, we need the slope

Pick any two points from the table. I'll pick the last two points since everything is positive here.

m = (y2 - y1)/(x2 - x1)

m = (17 - 9)/(5 - 3)

m = 8/2

m = 4

The slope is 4

Use this slope value along with (x1,y1) = (3,9) with point slope form

y - y1 = m(x - x1)

y - 9 = 4(x - 3)

y = 4(x-3) + 9

y = 4x-12 + 9

y = 4x-3

The correct equation is y = 4x-3

Plugging in x = -1 leads to

y = 4x-3

y = 4(-1)-3

y = -4-3

y = -7

Which is what the table shows. I'll let you check the other x values in the table.

User Cristian Scheel
by
5.2k points
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