Question

Solve the two-step equation.

-9x + 0.4 = 4

Which operation must be performed to move all the constants to the right side of the equation? _________
A. Add 0.4
B. Add 4
C. Subtract 0.4
D. Subtract 4

Then, which operation must be performed to isolate the variable? ____________
A. Add -9 on both sides
B. Subtract -9 on both sides
C. Multiply by -9 on both sides
D. Divide by -9 on both sides

The solution to the equation is x = _______.

Answer 1

To solve the equation -9x + 0.4 = 4, we subtract 0.4 (option C) and divide both sides by -9 (option D), yielding the solution x = -0.4.

Step-by-step explanation:

To solve the two-step equation -9x + 0.4 = 4, we must perform certain algebraic operations to isolate the variable x. First, we need to move all the constants to the right side of the equation. This is done by subtracting 0.4 from both sides of the equation, which aligns with option C.

The next step is to isolate the variable x. This can be achieved by dividing both sides by -9, in accordance with option D. This will leave us with the expression x on one side of the equation.

Performing these operations step by step:

1. Subtract 0.4 from both sides: -9x + 0.4 - 0.4 = 4 - 0.4, simplifying to -9x = 3.6.
2. Divide both sides by -9: -9x / -9 = 3.6 / -9, which simplifies to x = -0.4.

Therefore, the solution to the equation is x = -0.4.