Math 6A (Periods 1 & 2)

Equations: Decimals  8-4

You can use transformations to solve equations which involve decimals
Solve 0.42 x = 1.05
Divide both sides by 0.42
.42x/.42 = 1.05/.42
now, do side bar and actually divide carefully and you will arrive at
x = 2.5

1.6n = 3.6
1.6n/1.6 = 3.6/1.6
Carefully do the math and you find that
n = 2,25
If you need to-- practice with decimals! You need to be able to divide and multiply accurately!


Solve: n/.15 = 92
multiply both sides by .15 to undo the division
(n/.15)(.15) = 92 (.15)
Again, do a sidebar for your calculations and you will arrive at
n = 13.8


n + 0.519 = 0.597
we need to subtract 0.519 from both sides
n = 0.078

x - 0.323 = .873
we need to add 0.323 to both sides
x = 1.196


Reminder: the ultimate objective is applying transformations to an equation is to obtain an equivalent equation in the form x = c
(where c is a constant.)

Also remember that the understood (invisible) coefficient of x in the equation x = c is 1.

[Can you picture the poster in the front of the room?]