Question 878472
Instead of {{{0.05b^2-45b-920}}}, I'm going to write {{{0.05x^2-45x-920}}}


For {{{0.05x^2-45x-920}}}, we see {{{a = 0.05}}}, {{{b = -45}}}, {{{c = -920}}}  


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Use the quadratic formula to solve for x


{{{x = (-b+-sqrt(b^2-4ac))/(2a)}}}


{{{x = (-(-45)+-sqrt((-45)^2-4(0.05)(-920)))/(2(0.05))}}} Plug in {{{a = 0.05}}}, {{{b = -45}}}, {{{c = -920}}}  


{{{x = (45+-sqrt(2025-(-184)))/(0.1)}}}


{{{x = (45+-sqrt(2025+184))/(0.1)}}}


{{{x = (45+-sqrt(2209))/0.1}}}


{{{x = (45+sqrt(2209))/0.1}}} or {{{x = (45-sqrt(2209))/0.1}}}


{{{x = (45+47)/0.1}}} or {{{x = (45-47)/0.1}}}


{{{x = 92/0.1}}} or {{{x = -2/0.1}}}


{{{x = 920}}}    or    {{{x = -20}}}


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The two solutions are {{{x = 920}}}    or    {{{x = -20}}}