Twice a number increased by seven is three less than three times the same number

Answer 1

Go slow and see what it's telling you. If n is our number, twice that is 2n. Increasing 2n by 7 gives us 2n + 7. That's not 9, because 2 is being multiplied by something unknown before we add 7. 2 + 7 = 9 and 2n + 7n = 9n, but 2n + 7 is just that.

Well, "is" is "=".

Three times the same number is 3n. Three less than that is 3n - 3, again not equal to 0.

2n + 7 = 3n - 3