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The difference between the roots of the quadratic equation x^2−14x +q=0 is 6. Find q.

User KingNestor
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1 Answer

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Answer: q = 40

Explanation:

Given the quadratic formula as

x = [-b +/-√(b^2 -4ac)]/2a

b = -14

a = 1

c = q

Difference d between the two roots.

d = [-b + √(b^2 -4ac)]/2a - [-b -√(b^2 -4ac)]/2a

d = 2√(b^2 -4ac)/2a

d = √(b^2 -4ac)/a

And d = 6

Substituting the values of a,b and c. We have;

6 = √[(-14^2) - (4×1×q)]

Square both sides

6^2 = 196 - 4q

4q = 196 - 36

q = 160/4

q = 40

The equation becomes

x^2 - 14x + 40 = 0

User GiladG
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