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How to solve the equation 2x^2 -1 =5x?

2 Answers

4 votes

Answer:

x = 2.68, x = -0.186 is the answer , i got a 100% on my test

Explanation:

User Guy Brooker
by
6.8k points
3 votes

Answer:

x = 2.68, x = -0.186

Explanation:

We are given the following equation that we are to solve:


2 x ^ 2 - 1 = 5 x

Rearranging this quadratic equation to get:


2 x ^ 2 -5 x - 1 = 0

Solving it by using the quadratic formula as we cannot find any factors for it.


x= (-b \pm √(b^2-4ac) )/(2a)


x=(-(-5) \pm (-5)^2-4(2)(-1))/(2(2))


x=(5 \pm√(25+8) )/(4)


x=(5+√(33) )/(4),
x=(5-√(33) )/(4)

x = 2.68, x = -0.186

User Isosceleswheel
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