Open Middle®
Directions: Using the digits 1 to 9, at most one time each, place a digit in each box to create a linear equation that has an x- and y-intercept with integer values.
Hint
When finding an x – intercept, how does the coefficient of the x-variable operate with the constant value?
When finding a y-intercept, how does the coefficient of the y-variable operate with the constant value?
Answer
There are many possible solutions:
Example:
2x + 3y =6
1x + 4y = 8
3x + y =9
Source: Jeffrey Mashbitz
Lol. I thought the instructions were to use *all* the digits, 1–9. I recalled that 123456789 is divisible by 3, so with a little thought realized this would work:
3x + 6y = 1457892
Maybe a challenge question?
Well now that’s an interesting twist. Thanks for sharing that!