Question 1017694
A)4x^2 – 27 = 0
4x^2=27
square root of both
2x=sqrt (27)
x=(1/2) sqrt (27)
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B) 4x^2 – 8x – 5 = 0
factor
(2x-5)(2x+1)=0
x=5/2,-1/2
{{{graph(300,200,-10,10,-10,10,4x^2-8x-5)}}}
C) 4x^2 – 8x – 12 = 0
first factor out a 4
4(x^2-2x-3)=0
This factors into 4(x-3)(x+1)=0, x=3,-1
D) 4x^2 – 9x – 7 = 0
Use quadratic formula here.
x=(1/8)(9+/-sqrt (81+112)); sqrt 193=13.89
numerical (1/8)(9+/-13.89)=2.86 , -0.61
{{{graph(300,200,-10,10,-10,10,4x^2-9x-7)}}}