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Which equation has the solutions x = 1 plus-or-minus StartRoot 5 EndRoot?

2 Answers

4 votes

Answer:

Letter D

Explanation:

EDGE2021

User Nesiseka
by
2.9k points
0 votes

Answer:

The quadratic equation is x^2-2x-4

Explanation:

We want to know the equation that has the solution below;

x = 1 ± √5

This means x = 1 + √5 or 1 - √5

The equation would thus be;

(x-1-√5)(x-1+ √5)

= x(x-1+ √5)-1(x-1+ √5)-√5(x-1+ √5)

Opening the brackets we have ;

x^2-x+ √5x-x + 1 -√5-√5x+ √5-5

collecting like terms we have;

x^2-2x+1-5

= x^2-2x-4

User Steve Eggering
by
3.1k points