Answer:
-3x+21
Step-by-step explanation:
Using distributive property
(-3*x)-(-3*7)
-3x-(-21)
-3x+21
Answer:
x=23
Step-by-step explanation:
You have to multiply -3 to both the x and -7.
that is how you get -3x + 21. (because -3 time -7 = Positive 21.)
then you want to get x by itself which then you would add 3 to both sides giving you X=23.