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If: y = x^2 -8x +7 and y = kx -2

Then: X^2 -8x +7 = kx -2

Transposing terms: x^2 +(-8x -kx) +9 = 0

Using the discriminant: (-8 -k)^2 -4(1*9) = 0

Expanding brackets: 64 +16k +k^2 -36 = 0

Collecting like terms: k^2 +16k +28 = 0

Factorizing the above: (k +2)(k +14) = 0 meaning k = -2 or -14

Therefore the possible values of k are: -2 or -14

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6y ago
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6y ago

They are -14 and -2.

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Q: What are the possible values of k when the line y equals kx -2 is a tangent to the curve y equals x2 -8x plus 7?
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A tangent is a line that just touches a curve at a single point and its gradient equals the rate of change of the curve at that point.


What are the possible values of k in the line y equals kx -2 which is tangent to the curve y equals x squared -8x plus 7?

The possible values for k are -2 and -14 because in order for the line to be tangent to the curve the discriminant must be equal to 0 as follows:- -2x-2 = x2-8x+7 => 6-x2-9 = 0 -14x-2 = x2-8x+7 => -6-x2-9 = 0 Discriminant: 62-4*-1*-9 = 0


What is the value of y when y equals 2x plus 1.25 is a tangent to the curve y squared equals 10x?

If the line y = 2x+1.25 is a tangent to the curve y^2 = 10x then it works out that when x = 5/8 then y = 5/2


What are the possible values of k when y equals kx -2 which is tangent to the curve of y equals x squared -8x plus 7 showing work?

The gradient to the curve y = x2 - 8x + 7 is dy/dx = 2x - 8The gradient of the tangent to the curve is, therefore, 2x - 8.The gradient of the given line is kTherefore k = 2x - 8. That is, k can have ANY value whatsoever.Another Answer:-If: y = kx-2 and y = x2-8x+7Then: x2-8x+7 = kx-2 => x2-8x-kx+9 = 0Use the discriminant of: b2-4ac = 0So: (-8-k)2-4*1*9 = 0Which is: (-8-k)(-8-k)-36 = 0 => k2+16k+28 = 0Using the quadratic equation formula: k = -2 or k = -14 which are the possible values of k for the straight line to be tangent with the curve


How do you find the point of tangency?

A tangent is an object, like a line, which touches a curve. The tangent only touches the curve at one point. That point is called the point of tangency. The tangent does not intersect (pass through) the curve.

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What are the possible values of k in the line y equals kx -2 which is tangent to the curve y equals x squared -8x plus 7?

The possible values for k are -2 and -14 because in order for the line to be tangent to the curve the discriminant must be equal to 0 as follows:- -2x-2 = x2-8x+7 => 6-x2-9 = 0 -14x-2 = x2-8x+7 => -6-x2-9 = 0 Discriminant: 62-4*-1*-9 = 0


What is the value of y when y equals 2x plus 1.25 is a tangent to the curve y squared equals 10x?

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What are the possible values of k when y equals kx -2 which is tangent to the curve of y equals x squared -8x plus 7 showing work?

The gradient to the curve y = x2 - 8x + 7 is dy/dx = 2x - 8The gradient of the tangent to the curve is, therefore, 2x - 8.The gradient of the given line is kTherefore k = 2x - 8. That is, k can have ANY value whatsoever.Another Answer:-If: y = kx-2 and y = x2-8x+7Then: x2-8x+7 = kx-2 => x2-8x-kx+9 = 0Use the discriminant of: b2-4ac = 0So: (-8-k)2-4*1*9 = 0Which is: (-8-k)(-8-k)-36 = 0 => k2+16k+28 = 0Using the quadratic equation formula: k = -2 or k = -14 which are the possible values of k for the straight line to be tangent with the curve


What are the values of k when the line of y equals kx -2 is a tangent to the curve of y equals x squared -8x plus 7?

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