UNITS OF WORK

In science, when you are using the formulas for force
(force = mass x acceleration)
or for momentum
(momentum = mass x velocity)
you will solve these equations the same way you would in math class.

On the Ohio Graduation Test "OGT" you will be allowed to use the calculator provided for the test. In this section you can review the basic operations with the calculator as well as how to input negative numbers and fractions. 
To input a negative number you use the key in the last row to the left of the key. You input the number first then the key. Warning: Do not use the subtraction key for negative numbers. 
Example: 75.93

Keystrokes:

Display: 75.93

To multiply use the key which is in the sixth row and the fourth column. 
72 x ( 89) =

Keystrokes:

Display: 6408

4.6 x 8.62 =

Keystrokes:

Display: 39.652

9/5 x 15/18 =

Keystrokes:

Display: 1_1
2

Mixed Number: 1
1/2

To convert to an improper fraction, do not clear the display.

Keystokes:

Display: 3
2

Improper Fraction: 3/2

To divide use the key which is in the sixth row and the fifth column. 
16
44 =

Keystrokes:

Display: 0.363636363

Decimal Form: 0.36

If you need your answer in fractional form you can use the
instead
of the
key.

Keystrokes:

Display:  4
11

Fractional Form:  4/11

34.01
16 =

Keystrokes:

Display: 2.125625

Make sure you read the directions of each problem carefully so you will
know what decimal place to round your answer to.

15
5/9 =

Keystrokes:

Diplay: 27

ax = b

To solve multiplication equations you have to divide both sides of the
equation by the number you are multiplying the variable by.

3x = 21

Solve: Divide both sides of the equation by 3
(not 3x just 3)

3x = 21
3 3

Solution: Since 3/3 is 1 you have 1x, which is written as just x,

on
the right handside of the =.

And 21/3
= 7 you have 7 on the left hand side of the =.

x
= 7

Check: Substitute 7 in for x in the original equation 3x = 21

3(7)
= 21 and 21 = 21 so
7
is the answer to the equation.

 4.79 x = 8.21

Solve: Divide both sides of the equation by  4.79
(not
 4.79x just  4.79)


4.79 x = 8.21

4.79  4.79

Solution: Since  4.79/ 4.79 is 1 you have 1x,
which
is written as just x,
on
the right hand side of the =.

And 8.21/
4.79 = 1.713987474
(round
to 2 places after the decimal)
so
you have 1.71 on the left hand side of the =.

x = 1.71

Check: Substitute 1.71 in for x in the original equation

4.79 x = 8.21

 4.79
(1.71) = 8.21 and 8.19 = 8.21

so
1.71
is the answer to the equation.

(Remember we had to round our solution to 2 decimal
places
so in the check so there is a slight rounding error.)

Exercise 1: 5x = 60

Exercise 2: 2.6x = 17.8
(Round
answer to 2 places after the decimal.)

Exercise 3: 7x = 49.63
(Round
answer to 2 places after the decimal.)

Exercise 4: 10x = 6
(Leave
your answer in reduced fractional form.)

Hit next to check your answers.

Exercise 1: Divide both sides by 5

x
= 12

Exercise 2: Divide both sides by 2.6

x
= 6.85

Exercise 3: Divide both sides by 7

x
= 7.09

Exercise 4: Remember all fractions are a division problem,
so
divide both sides by 10.

6
divided by 10 in fractional form is 6/10,

this
reduces to 3/5.

x
= 3/5
