Quadratic equation 2x^2+7x-1=0?

Question

Quadratic equation 2x^2+7x-1=0?

Answer 1

x = 0.137458609,

x = -3.637458609

Answer 2

Use general solution: x = [-b ± √(b² - 4ac)] / 2a   when you have to solve for solution of ax² + bx + c = 0

So, by applying that formula,

x = {-7 ± √[49 -( -8)]} / 2(2)

= (-7 ± √57) / 4

Answer 3

2x^2 + 7x - 1 = 0

x = [-b ±√(b^2 - 4ac)]/2a

a = 2

b = 7

c = -1

x = [7 ±√(49 + 8)]/4

x = [7 ±√57]/4

x ≈ [7 ±7.54]/4

x ≈ [7 + 7.54]/4

x ≈ 14.54/4

x ≈ 3.635

x ≈ [7 - 7.54]/4

x ≈ -0.54/4

x ≈ -0.135

∴ x ≈ -0.135 , 3.635

Answer 4

325

Answer 5

2x^2+7x-1=0

x^2+(7/2)x-1/2=0

(x+7/4)^2-49/16-1/2=0

(x+7/4)^2=57/16

x+7/4=(57^1/2) / 4

x=(57^1/2-7)/4

Answer 6

:s well you definitely can't factorise this into 2 brackets...

Completing the square then:

2x^2 + 7x -1 = 0

2[x^2 + 7/2 -1/2] = 0

2[(x + 7/4)^2 - 49/16 - 1/2] = 0

2[(x + 7/4)^2 - 57/16] = 0

2(x + 7/4)^2 - 57/8 = 0

2(x + 7/4)^2 = 57/8

(x + 7/4)^2 = 57/16

x + 7/4 = +- sqrt(57)/4

x = [-7 +- sqrt(57)]/4

* +- is the same as plus or minus (+ above - when handwritten)

Hope that's right... do you have the answer handy?

I have the same answer as the one above me, just looks slightly different

Answer 7

done these last month- so boring!!!

2x^2=2x x 2x=4x+7x=

11x+1