How do you solve 45a = 9?

2 Answers
Apr 15, 2018

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

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"harrcolor(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