m = 5 and n = 3
let f(x) = 2x³ - mx² + nx - 2 , then
f( - 1 ) = - 2 - m - n - 2 = - 12
f(2 ) = 16 - 4m + 2n - 2 = 0
Tidying up the 2 equations
- m - n = - 8 → (1)
- 4m + 2n = - 14 → ( 2)
multiply equation ( 1) by 2
- 2m - 2n = - 16 → ( 3 )
add ( 2 ) and ( 3 ) term by term
-6m = - 30 ⇒ m = 5 ( substitute m = 5 into (2 )
- 20 + 2n = - 14
2n = 6 ⇒ n = 3
He answer is d which is 25
9514 1404 393
Answer:
(x, y) = (-3, -13) or (-8, -23)
Step-by-step explanation:
The values for y can be equated and the resulting quadratic solved by factoring.
2x -7 = x^2 +13x +17
0 = x^2 +11x +24 . . . . . . subtract 2x-7
0 = (x +8)(x +3) . . . . . . . .factor*
The values of x that make these factors zero are x=-8 and x=-3. The corresponding values of y are ...
y = 2(-8) -7 = -23
y = 2(-3) -7 = -13
The solutions are ...
(x, y) = (-8, -23) and (-3, -13)
_____
* The constants in the binomial factors are factors of 24 that total 11. You know that ...
24 = 1×24 = 2×12 = 3×8 = 4×6
The sums of these factors are 25, 14, 11, 10. The factors 3 and 8 are the constants in the binomial factors of the quadratic.
"24" is the constant in the quadratic. "11" is the coefficient of the x term.
Answer: 60
Step-by-step explanation: