Changing the Subject of Formulas: A Guide to Isolating Variables

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