Mrs. Porte wrote the equation below on the board.
ax+ 7 = 8x + b
Enter values of a and b for which x = 9 is a solution of Mrs. Porte's equation.

b=-65

Step-by-step explanation:

7 = 8x+b

Put in 9 for x

7 = 8(9) + b

Multiply.

7=72 + b

subtract 72 from both sides to get b by itself.  

(7-72) = (72-72) + b

Simplify.

-65 = b

a. is correct

exa:

)

3+11

14

step-by-step explanation:

from this example, we can see that subtracting with integers is the same as adding the opposite. we can solve using a number line or by using the saying "keep, change, change" to us solve. it is important to remember that we can subtract a negative and end up with a larger number than we started with.