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9 votes
9 votes
Solve the equation 2x^{2}-12x-14=x^{2}-8x2x 2 −12x−14=x 2 −8x to the nearest tenth

PLEASE HELP

User Salvador Medina
by
3.2k points

1 Answer

6 votes
6 votes

Answer:

x = 6.2 or -2.2

Explanation:

Given:

2x² - 12x - 14 = x² - 8x

Collect like terms

2x² - x² - 12x + 8x - 14 = 0

x² - 4x - 14 = 0

a = 1

b = -4

c = -14

x = -b ± √b² - 4ac / 2a

= -(-4) ± √(-4)² - 4(1)(-14) / 2(1)

= 4 ± √16 -(-56) / 2

= 4 ± √16 + 56 / 2

= 4 ± √72 / 2

= 4 ± 6√2 /2

= 4/2 + 6√2/2 or 4/2 - 6√2/2

= 2 + 3√2 or 2 - 3√2

= 2 + 4.2426406871192 or 2 - 4.2426406871192

= 6.2426406871192 or -2.2426406871192

Approximately,

x = 6.2 or -2.2

User Andrei Stalbe
by
3.1k points
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