Find the possible values of the constant
k, if the roots of the quadratic equation
x-(k+2)x+4=0 are equal.
8. if a and b are the roots of the quadratic
equation px' +qx+r=0, express
(2++b? ) in terms p, q andr.
if y = 2x - 3x - 1, find the minimum
value of y and the corresponding value
ofx.
10. given that y = 2 - 3x - 4x, find the
maximum value of y and the value of x
at which y is maximum.

pls answer no 7,9 and10

Step-by-step explanation:

7

x - (k+2)x + 4

Since the roots are equal, b^2 - 4ac =0

a =x, b=k+2, c =4

(k+2)^2 - 4(1×4) =0

K^2 + 4k + 4-16 =0

K^2 +4k - 12=0

K^2 +6k - 2k - 12 =0

K(k + 6) - 2(k +6)=0

(k-2)(k +6) =0

K =2 or - 6

option a.

step-by-step explanation:

if you look closely at the graph, we can notice that the function is not defined at two different points.

if you look at functions b and c, you will notice that both functions are not defined at just one point. the function b is not defined at x= -5/2 and function c is not defined at x=-5. both options are discarded, given that our function should not be defined at two fiferent points.

now, if you look closely at the graph you will notice that the function sketched is not defined at x=5 and x=-2.

step-by-step explanation: