Question

Write three equations whose solution is x=3.5

Answer 1

Answer:

• 1. 2x + 23 = 30

• 2. 3x + 19.5 = 30

• 3. (10x - 20)/ 5 = 3

Explanation:

Work backward:

1. 2x + 23 = 30

Start:

• x = 3.5

Multiply the equation by 2:

• 2x = 2 (3.5)
• 2x = 7

Subtract 30 from both sides

• 2x - 30 = 7 - 30
• 2x - 30 = -23

Add 23 and 30 to both sides:

• 2x + 23 = 30

2. 3x + 19.5 = 30

Start:

• x = 3.5

Add 6.5 to both sides:

• x + 6.5 = 10

Multiply by 3:

• 3(x + 6.5) = 30

Distributive property:

• 3x + 19.5 = 30

3. (10x - 20)/ 5 = 3

Start:

• x=3.5

Multiply by 10:

• 10x = 35

Subtract 20:

• 10x - 20 = 15

Divide by 5:

• (10x - 20)/ 5 = 15/5

• (10x - 20) / 5 = 3