Answer:
not sure but this should be it
Answer:
-2x+2y+3z=0
-2x-y+z=-3
2x+3y+3z=5
---------------
-2x+2y+3z=0
-2x-y+z=-3
---------------- Subtract
3y + 2z = 3 Eqn A
=========================
-2x-y+z=-3
2x+3y+3z=5
---------------- Add
2y + 4z = 2
6y + 4z = 6 Eqn A times 2
------------------------------------ Subtract
-4y = -4
y = 1
-----------------
z = 0
-------------------
x = 1
7<n<8 is the right answer
Move all terms to one sides
3x^2 - 14x - 5 = 0
Split the second term in 3x^2 - 14x - 5 into two terms
3x^2 + x - 15x - 5 = 0
Factor out the common terms in the first two terms, then in the last two terms;
x(3x + 1) - 5(3x + 1) = 0
Factor out the common term 3x + 1
(3x + 1)(x - 5) = 0
Solve for x;
<u>x = -1/3, 5</u>