How do you multiply #(4\times 10^ { - 3} ) ( - 2\times 10^ { 8} )#?

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Answer 1 · 2018-01-04T11:36:54

See a solution process below:

First, we can rewrite this expression as:

#(4 xx -2)(10^-3 xx 10^8) =>#

#-8(10^-3 xx 10^8)#

Next, we can use this rule for exponents to multiply the 10s terms:

#x^color(red)(a) xx x^color(blue)(b) = x^(color(red)(a) + color(blue)(b))#

#-8(10^color(red)(-3) xx 10^color(blue)(8)) =>#

#-8 xx 10^(color(red)(-3)+color(blue)(8)) =>#

#-8 xx 10^5#

Or, in standard notation

#-800,000#

Answer 2 · 2018-01-04T13:19:09

#-800,000# or #-8xx10^5#

#(4xx10^-3)(-2xx10^8)#

#:.=(4xx0.001)(-2xx100000000)#

#:.=(0.004)(-200000000)#

#:.=-800,000# or #-8xx10^5#