How do you #-4/5 xx (-1/2)#?

Question

1030 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-09-16T17:28:56

#2/5#

When multiplying fractions..

#rarr# change mixed numbers to improper fractions. (not in this case)

#rarr# multiply the signs: (odd #rarr# neg, even #rarr# pos)

#rarr# cancel if possible, a numerator with a denominator across X

#rarr "top x top"/"bottom x bottom"#

#-4/5 xx-1/2" "larr# sign will be positive

=#+ cancel4^2/5xx1/cancel2" "larr# cancel where possible

=#2/5#

Answer 2 · 2016-09-18T18:39:56

#2/5#

Everything is multiply so we can split this:

#color(blue)("First, consider the signs. ")#

We have #" negative "xx" negative "=" positive"#

#color(chocolate)("So the answer is positive.")#

'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

#color(blue)(" Second, consider just the numbers.") #

#4/5xx1/2" "=" "(4xx1)/(5xx2)" "=" "4/10#

#=>(4-:2)/(10-:2) =color(chocolate)(2/5)#
'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#color(blue)("Putting it all together")#

#color(green)(-4/5xx(-1/2)" "=" "+2/5)#