Question #97873

1 Answer
Jan 29, 2017

Answer:

#d=6#

Explanation:

Given:#" "2d-5=7#

Determine the value of #d#

Add #color(magenta)(5)# to both sides. This turns the 5 on the left of the = into 0

#color(green)(2d-5=7" "->" "2d-5color(magenta)(+5)=7color(magenta)(+5))#

But #-5+5 = 0# giving:

#" "->" "color(green)(2d+0=12)#

Divide both sides by #color(magenta)(2)#. This turns the 2 in #2d# into 1

#" "color(green)( ->" "2/(color(magenta)(2)) xx d=12/(color(magenta)(2))#

But #2/2=1# giving

#" "color(green)(->" "1xxd=6)#
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#d=6#