Q:

Worth TONS of points!!! This test is super important so do not give me guesses be at least 95% sure of your answer. Answer all parts for brainliestLet f(x)=7x^3-2x-12 and g(x)=-3x^3-8x^2+10x. What is the function rule for (f+g)(x)Let f(x)=6-5x and g(x)=6x^2+x. What is the function rule for (fg)(x)Let x^2+18x=44. What values make an equivalent number sentences after completing the square? x^2+18_____=_______ What is the solution to the system of linear equations?2x+4y=203x+2y=26Solve the system of equations (there is more than one correct solution)14x+y=-4y=3x^2-11x-4 Factor. x^2-6x+8 Enter your answer in the box x^2-6x+8= ( , ) ( , )Let f(x)=x^2-6x- 27 Enter the x-intercepts of the quadratic function in the boxes.Answer all of these parts for lots of points AND brainliest! :)

Accepted Solution

A:
1. (f+g)(x)=7x^3-3x^3-8x^2+10x-2x-12=4x^3 - 8x^2 + 8x - 12

2. fg(x)=6-5(6x^2+x)=6-30x^2-5x

3. x^2+18x=44   | +36
    x^2+18x+36=44+36
    (x+6)^2=80

4. 2x+4y=20   |:2
    x+2y=10
    3x+2y=26
-----------------
   3x-x=26-10
   2x=16
   x=16:2
x=8
x+2y=10
8+2y=10
2y=10-8
2y=2
y=2:2
y=1

5. 14x+y= -4
     y= -4 -14x
   y=3x^2-11x-4
   -4 -14x = 3x^2-11x-4      |+4
       -14x=3x^2-11x    |+14x
       0=3x^2+3x
      3x(x+1)=0
x=0 or x=-1 is the solution

6. x^2-6x+8= x^2-2x-4x+8= x(x-2)-4(x-2)=(x-2)(x-4)

7. x^2-6x-27=0
     x 1= (-6+V36+4*27)/2= (-6+V144)/2= (-6+12)/2=6/2=3
    x2= (-6-12)/2= -18/2= -9

the point are ( 3,0) and (-9.0)