Question 180847
(z-6)^2-40=0 

z^2-12z+36-40 =0

z^2 - 12z - 4 = 0
Use the quadratic formula to get:

z = [12 +- sqrt(12^2 - 4*1*-4)]/2

z = [12 +- sqrt(160)]/2

z = [12 +- 4sqrt(10)]/2

z = 6 +- 2sqrt(10)
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2x^2+7x+2=0 

Use the quadratic forula to get:

x = [-7 +- sqrt(7^2 -4*2*2)]/4

x = [-7 +- sqrt(33)]/4

x = (-7/4) +- (1/4)sqrt(33)
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Cheers,
Stan H.