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# Multi-Step Equations – Smallest (or Largest) Solution

Directions: Use the digits 1 to 9, at most one time each, to create an equation where x has the smallest (or greatest) possible value.

### Hint

Where do you want to put the smaller (or larger) numbers?
How does choosing the coefficient or constant affect the variable’s value?

The smallest solution I’ve found so far is x = -70
(9/1)(3x + 8) + 4x = 6x + 2

The largest solution I’ve found so far is x = 8:
(4/8)(6x + 2) + 1x = 3x + 9

Source: Daniel Luevanos

## Square Root Expression

Directions: Use the digits 1 to 9, at most one time each, to fill in …

1. Here is an equation where x=20.

(9/3)(1x+8)+2x=6x+4

2. Here is an equation where x=61

(1/7)(8x+2)+5x=6x+9

3. I think the solution above where the solution is x = -70 is actually a case where 25x = -70, which would make x = -2.8. (9/1)(3x + 8) + 4x = 6x + 2 gives us 27x + 72 + 4x = 6x + 2, which then simplifies to 31x + 72 = 6x + 2, which further simplifies to 25x = -70. Did I miss something in my calculations?

4. One of my students found several ways to make the equation true for any number, so that you could use 100 or 1,456,918 and it would still be true:
9/3(1x + 2) + 4x = 7X + 6
6/3(2x + 4) + 1x = 5x + 8
6/2(1x + 3) + 4x = 7x + 9

Another student tried to find the lowest possible and got x = -44.
7/8(1x + 4) + 5x = 3x + 9

5. If you define smallest to be closest to zero, then 8/2(9x + 1) + 6x = 3x + 4 is zero.

6. 2/9(5x+1)+6x=7x+8 is the best answer. X=70. All you have to do is just try.