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Point K is between points J and L. If JK=x2−4x, KL=3x−2, and JL=28, find JK and KL.

User Tonyrobbins
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1 Answer

24 votes
24 votes

Answer:

Explanation:

JK + KL = JL

x² - 4x +3x - 2 = 28

x² - x - 2 = 28

x² - x -2 - 28 = 0

x² - x - 30 = 0

Sum = -1

Product = -30

Factors = -6 , 5 {-6 + 5 = -1 and (-6)*5 = -30}

x² + 5x - 6x - 30 = 0 {Rewrite the middle term}

x(x + 5) - 6(x + 5) = 0

(x + 5)(x - 6)= 0

x -6 = 0 {X +5 = 0 is ignored as measurement will not be negative}

x = 6

JK = x² - 4x

= 6² - 4*6

= 36 - 24

JK = 12

KL = 3x -2

= 3*6 - 2

= 18 - 2

KL = 16

User Utek
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