Isolating Variables and Solving Equations

To find the value of D that makes the equation true

To eliminate all variables from the equation

To find the value of D that makes the equation false

To convert the equation into a quadratic form

Multiply both sides by 7.4

Add 4 to both sides

Subtract 7.4 from both sides

Divide both sides by 4

Because 7.4 is divided by D

Because 7.4 is multiplied by D

Because 7.4 is added to D

Because 7.4 is subtracted from D

Addition

Subtraction

Multiplication

Division

6

7

8

9

Divide both sides by 10

Add 10 to both sides

Multiply both sides by 10

Subtract 10 from both sides

-40 + 74d = 558

-4 + 7.4d = 55.8

4 + 7.4d = 55.8

40 + 74d = 558

-7

-6

6

8

By checking if -4 + 7.4 * D equals 0

By checking if -4 + 7.4 * D equals 100

By checking if -4 + 7.4 * D equals 55.8

By checking if -4 + 7.4 * D equals -55.8

To ensure the solution is incorrect

To confirm the solution satisfies the original equation

To find an alternative solution

To simplify the equation further