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SOLVE FOR VARIABLE
1.
Determine what answer will look like
2.
3.
Eliminate Grouping Symbols (Distribute)
Eliminate Fractions, if any
4.
5.
6.
Add or subtract to isolate variable on one side
Divide both sides by Coefficient of the variable
Check your solution

OBJECTIVE: TO BE ABLE TO SOLVE FOR
VARIABLE
2.8 LITERAL EQUATIONS AND DIMENSIONAL
ANALYSIS
CLE 3102.3.5 MANIPULATE FORMULAS AND SOLVE LITERAL
EQUATIONS.
CLE 3102.4.2 APPLY APPROPRIATE UNITS OF MEASURE AND
CONVERT MEASURES IN PROBLEM SOLVING SITUATIONS.
SPI 3102.4.4 ; CONVERT RATES AND MEASUREMENTS
.

USE A FORMULA TO SOLVE PROBLEM

A car’s fuel economy is given by the formula, where m is the number of miles driven and g is the number of gallons of fuel used.

1.
If Claudia’s car has an average fuel consumption of 30 miles per gallon and she used 9.6 gallons how far did she drive?
What variable should you solve for?
m
2.
3.
Solve for the variable.’
Solve for the amount

USING FORMULA

The formula for the volume of a cylinder is , where r is the radius of the cylinder and h is the height.

Solve the formula for h.
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What is the height of a cylindrical swimming pool that has a radius of 12 feet and a volume of 1810 cubic feet?

SOLVING EQUATIONS AND FORMULAS

Solve an equation for a specific variable

Solve 7x – 2z = 4 – x for x
+x +2z

Solve 3x – 4y = 7 for y
-3x
8x = 2z + 4 x = 1/8(2z + 4)
-4y = 7 – 3x y = -1/4(7 -3x)

Use Dimensional Analysis
CHIMPANZEES The average weight of the chimpanzees at a zoo is 52 kilograms. If
1 gram ≈ 0.0353 ounce, use dimensional analysis to find the average weight of a chimpanzee in pounds.
(Hint: 1 lb = 16 oz) weight of chimpanzee kilograms to grams
52 kg × × grams to ounces
× ounces to pounds

EXAMPLE 4
Use Dimensional Analysis
Notice how the units cancel, leaving the unit to which you are converting.
52 kg × × × =
Answer: The average weight of a chimpanzee is about 115 pounds.

EXAMPLE 4
CHARITY Janet is walking 20 laps of a track in a relay to raise money for cancer research. If each lap is 350 meters, how many miles will Janet walk? (Hint: 1 meter  1.094 yards and 1 mile = 1760 yards)
A.
about 4.35 mi
B.
about 7 mi
C.
about 7.7 mi
D.
about 8 mi

ASSIGNMENT
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