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
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.
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
To find the possible values of ( k ) for which the line ( y = kx - 2 ) is tangent to the curve ( y = x^2 - 8x + 7 ), we need to set the two equations equal and solve for ( x ): ( kx - 2 = x^2 - 8x + 7 ). Rearranging gives us the quadratic equation ( x^2 - (k + 8)x + 9 = 0 ). For the line to be tangent to the curve, this quadratic must have exactly one solution, which occurs when the discriminant is zero: ((k + 8)^2 - 4 \cdot 1 \cdot 9 = 0). Solving this gives ( k + 8 = \pm 6 ), leading to possible values ( k = -2 ) and ( k = -14 ).
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
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
A line tangent to a curve, at a point, is the closest linear approximation to how the curve is "behaving" near that point. The tangent line is used to estimate values of the curve, near that point.
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.
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
To find the possible values of ( k ) for which the line ( y = kx - 2 ) is tangent to the curve ( y = x^2 - 8x + 7 ), we need to set the two equations equal and solve for ( x ): ( kx - 2 = x^2 - 8x + 7 ). Rearranging gives us the quadratic equation ( x^2 - (k + 8)x + 9 = 0 ). For the line to be tangent to the curve, this quadratic must have exactly one solution, which occurs when the discriminant is zero: ((k + 8)^2 - 4 \cdot 1 \cdot 9 = 0). Solving this gives ( k + 8 = \pm 6 ), leading to possible values ( k = -2 ) and ( k = -14 ).
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
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
If: y = kx -2 and y = x^2 -8x+7 Then the values of k work out as -2 and -14 Note that the line makes contact with the curve in a positive direction or a negative direction depending on what value is used for k.
Gradient to the curve at any point is the derivative of y = x2 So the gradient is d/dx of x2 = 2x. When x = 2, 2x = 4 so the gradient of the tangent at x = 2 is 4.
(2, -2)
You find the tangent to the curve at the point of interest and then find the slope of the tangent.
If: y = kx+1 is a tangent to the curve y^2 = 8x Then k must equal 2 for the discriminant to equal zero when the given equations are merged together to equal zero.
It is (-0.3, 0.1)