Changing the Subject of Formulas: A Guide to Isolating Variables

The video tutorial explains how to identify and change the subject of a formula. It covers basic concepts, such as isolating variables and using inverse operations, and provides examples to illustrate these techniques. The tutorial also addresses more complex formulas, demonstrating how to manipulate them to make a specific variable the subject. Key steps include expanding brackets, removing fractions, and applying inverse operations like addition, subtraction, multiplication, division, and square rooting.

What is typically the subject of a formula?

• A variable on the left side

• A mathematical operation

• A constant value

• A number on the right side

If you have the formula P = 4L, how would you find L if P is given?

• Subtract 4 from P

• Divide P by 4

• Multiply P by 4

• Add 4 to P

What is the inverse operation of multiplication?

• Square rooting

• Division

• Subtraction

• Addition

In the formula y = 12X - Z, what is the first step to make X the subject?

• Multiply by 12

• Subtract Z from both sides

• Divide by 12

• Add Z to both sides

When expanding brackets in a formula, what is the purpose?

• To isolate a variable

• To change the subject

• To simplify the equation

• To add complexity

In the equation a = 4(2B + C), what is the first step to make C the subject?

• Subtract 2B from both sides

• Divide by 4

• Expand the brackets

• Add 4 to both sides

What is the first step to isolate T in the equation y = 18T - 3/P?

• Subtract 3 from both sides

• Divide by 18

• Add 3 to both sides

• Multiply by P

What operation would you use to remove a square root in an equation?

• Square the equation

• Take the square root

• Multiply by 2

• Divide by 2

What is the general strategy for changing the subject of a formula?

• Use inverse operations

• Divide all terms by 2

• Add all terms together

• Multiply all terms by 2

Why is it important to deal with brackets first when changing the subject of a formula?

• To simplify the equation

• To isolate the subject

• To change the subject

• To make the equation more complex