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[15 points]find the least common multiple of the expressions: 1. 3x^2, 6x - 18 2. 5x, 5x(x +2) 3. x^2 - 9, x + 3 4. x^2 - 3x - 10, x + 2 explain if possible

In a two-digit number the units' digit is 7 more than the tens' digit. the number with digits reversed is three times as large as the sum of the original number and the two digits. find the number.

Which number line correctly shows 0.8 + 0.3?