CPhill

x = 2

y = 9

Here's the graph : https://www.desmos.com/calculator/t1rtnzcatm

The graph at the bottom left....

I/m assuming that this is

f(x) = -3 / [ 5x^3 ]

The  domain is (-inf, 0) U (0, inf)

And the range is the same

So  ⇒   "c"

7.

 c                  4

____   =   ______              cross-multiply

c - 5          c - 4

c (c - 4)  = 4(c - 5)

c^2 - 4c  = 4c - 20

c^2 - 8c + 20  = 0         complete the square on x

c^2 - 8c + 16  =  - 20 + 16

(c - 4)^2 =  -4        take both roots

c - 4   =  ±√-4

c - 4 = ±2i

c = 4 ±2i

Me???.....not disappointed....!!!!

4.What is the largest positive integer value of m such that the equation: 3x^2-mx+7=0
has no real solutions?

Thiw will occur when the discriminant is < 0      .....so....

m^2 - 4(3)(7)   < 0

m^2 - 84 < 0

m^2 <  84

m < sqrt (84)

So 

m = 9

OK....no prob....

3a  = 18          divide both sides by  3

a =  6    

Expand   (x + 2) (x - 3) ( x + 5) =

( x^2  - x - 6) ( x + 5)  =

x^3 - x^2  -  6x + 5x^2 - 5x - 30 =

x^3 + 4x^2 - 11x - 30

So

a = 4      and     b = -30

3.For what values of j does the equation (2x+7)(x-5)=-43+jx have exactly one real solution?

2x^2 - 3x - 35  =  -43 + jx      rearrange

2x^2 - (3 + j)x + 8 = 0

This will have one solution when the disriminant = 0  .......so....

(3 + j)^2 - 4(2)(8)  = 0

(3 + j)^2 - 64 = 0    

(3 + j)^2 = 64    take both roots

3 + j = ±8

3 + j = 8            or           3 + j = -8

j = 5                                   j = -11