How do you solve #45a = 9#?

2 Answers
Apr 15, 2018

Answer:

#a=1/5#

Explanation:

#45a=9# Isolate #a# (divide each side by #45#)
#(45a/45)=(9/45)# (#45/45=1#)
#a=9/45# Simplify 9/45 by dividing by #9#
#a=(9/9)/(45/9)#
#a=1/5#

Apr 15, 2018

Answer:

#a = 0.2#

Explanation:

To solve this type of equation, you need to isolate the variable by itself on one side of the equation. The variable in this problem is #a#.

#45a# means the same thing as #45 xx a#, so it means multiplication:

Since we see multiplication, we know that we have to use the opposite function, which would be division to isolate #a#.

OPPOSITES:

#color(red)"addition"##harr##color(blue)"subtraction"#
#color(red)"multiplication"# #harr# #color(blue)"division"#

So we will divide both sides by #45# to isolate #a#. Since the one side is already being multiplied by #45#, we can cancel the #45#'s:

#(cancel45a)/cancel45 = 9/45#

#a = 9/45#

Now just divide #9# by #45#

#a = 0.2#