How do you solve #8b^2-7=193#?

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Answer 1 · 2016-09-04T08:55:32

#b=+-5#

#8b^2-7=193#

or

#8b^2=193+7#

or

#8b^2=200#

or

#b^2=200/8#

or

#b^2=25#

or

#b=sqrt25#

or

#b=+-5#

Answer 2 · 2016-09-04T09:03:06

#x = +-5#

Usually a quadratic equation is solved by making it equal to 0.
However this is a special case where there is no term in #x#.

Isolate the #x^2# term by adding 7 to both sides.

#8x^2-7 color(blue)(+7)= 193 color(blue)(+7)#

#8x^2 = 200 " "larr div 8#

#x^2 = 25#

#x = +-sqrt25#

#x = +-5#