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That's the questions and the choices are.. :
1) x^2-14+50=0
2)X^2+14x+50=0
3)X^2-14x+48=0
4)X^2+14x+48=0

2006-11-26 21:45:48 · 11 answers · asked by Anonymous in Science & Mathematics Mathematics

11 answers

To find the equation, just substitute the 2 roots to the "Quadramagic formula" (...)
x² - (p + q)x + pq = 0
where p and q are the roots.

Hence, p = 7 + i and q = 7 - i. We substitute:
x² - [(7 + i) + (7 - i)]x + (7 + i)(7 - i) = 0

We add and multiply
x² - (14)x + (7² - i²) = 0

Since i² = -1, then
x² - 14x + 49 - (-1) = 0

then,
x² - 14x + 49 + 1 = 0

Therefore, the quadratic equation is
x² - 14x + 50 = 0

Therefore, the correct answer is 1).

^_^

2006-11-26 22:41:43 · answer #1 · answered by kevin! 5 · 0 0

X^2+14x+50=0

2006-11-27 00:03:09 · answer #2 · answered by Slimm D 3 · 0 0

2

2006-11-26 22:51:32 · answer #3 · answered by kumar 2 · 0 0

the equation

(x-7)^2 - i^2 = 0

or x^2-14x+ 50 = 0

2006-11-26 21:53:20 · answer #4 · answered by Mein Hoon Na 7 · 0 1

turn roots into aspects x = 7 ==> (x - 7) = 0 and (x - 7) is a element x = -2/3 ==> (x + 2/3) = 0, and (x + 2/3) is a element multiply the 2d element via 3 ==> (3x + 2) = 0 is the extra accepted element with x = -2/3 as a root (x - 7)(3x + 2) = 0 3x^2 - 19x - 14 = 0 is one such quadratic you additionally can multiply this via any actual variety to maintain an analogous roots

2016-12-29 13:24:55 · answer #5 · answered by Anonymous · 0 0

Using quad. formula on (1)

x = ( -b +- sqrt(b^2 - 4ac) ) / 2a, a=1, b=-14, c=50
x = ( -(-14) +- sqrt( (-14)^2 - 4(1)(50) ) ) / 2(1)
x = ( 14 +- sqrt(196 - 200) ) / 2
x = ( 14 +- sqrt(-4) ) / 2
x = ( 14 +- 2*sqrt(-1) ) / 2
x = 7 +- sqrt(-1)
x = 7+i, 7-i

try the quad. form on 2-4 to confirm that...

roots of (2) are -7+i & -7-i
root of (3) is +7
root of (4) is -7


Or get the answer directly by foiling

[x - (7- i)][x - (7 + i)]
x^2 - x(7- i) - x(7+i) + (7-i)(7+i)
x^2 - 7x + ix -7x -ix + 49 + 7i -7i -i^2
x^2 - 14x + 49 + i^2
x^2 - 14x + 49 - (-1)
x^2 - 14x + 50

2006-11-26 22:35:56 · answer #6 · answered by coop 2 · 0 0

answer

=x^2-x(sum 0f the roots)+(product of the roots)
=x^2-x(7+i+7-i)+(7+i)(7-i)
=x^2-x(14)+(49+1)
=x^2-14x+50

this is the right answer and it's not given in the choise list

2006-11-26 23:26:22 · answer #7 · answered by Anonymous · 0 0

No. 2 is the correct answer.

Given 7+ ì and 7- ì as roots.
→ x = 7+ ì (or) x = 7- ì
(x - 7- ì )(x - 7 + ì) = 0 [multiply out].
x² -7x + x ì - 7x + 49 - 7 ì - x ì + 7 ì - ì² = 0
x² -14x + 49 - ì² = 0
x² -14x + 49 - (√-1)² = 0
x² -14x + 49 + 1 = 0
x² -14x + 50 = 0

2006-11-26 22:58:41 · answer #8 · answered by Brenmore 5 · 0 0

Let a*x^2+b*x+c=0 be quadratic with roots m=7+i,n=7-i

=>-b/a=m+n=14 (Sum of the roots)

=>b/a=-14.....................................1


Also,
c/a=m*n=(7+i)(7-i)=49-(-1)=50 (Product of roots)

c/a=50........................2

As in all cases a=1,we have

c=50
b=-14

AND HENCE THE CORRECT OPTION IS ((((1))))

2006-11-27 01:00:23 · answer #9 · answered by amudwar 3 · 0 0

I think none of these is the right answer because when you get the products of the roots one part of the answer is 49 which is not given in any part of the choices.

2006-11-26 22:15:41 · answer #10 · answered by jdash01 3 · 0 1

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