Answer:
Step-by-step explanation:
Given that Human visual inspection of solder joints on printed circuit boards can be very subjective. Part of the problem stems from the numerous types of solder defects (e.g., pad non-wetting, knee visibility, voids) and even the degree to which a joint possesses one or more of these defects.
Let A- event inspect A found defective , B - inspector B found defective

,
a) Probability that the selected joint was judged to be defective by neither of the two inspectors=
b) Probability that the selected joint was judged to be defective by inspector B but not by inspector A
=

Hence
P(AB')\\=P(A)-P(AB)
= 0.0766-0.0624
=0.0142
Answer:
2x² + x - 1 = 0
a= 2 b= 1 c= -1
x = [ -b +- sqr rt( b^2 -4ac) ] / 2*a
x = -1 +- sqr rt (1 - 4 *2*-1) / 4
x1 = [ -1 + (sqr rt (1 +8)) / 4
x1 = ( -1 + sqr rt (9)) / 4
x1 = (-1 + 3) / 4
x1 = .5
x2 = (-1 -3) / 4
x2 = -4 / 4
x2 = -1
And to check that answer: http://www.1728.org/quadratc.htm
Step-by-step explanation:
The term in that equation is 3x 7x and -9 hope this helps