Answer:
Part A: a. the point 3 units to the left of 7
Part B: b. -4
Step-by-step explanation:
Part A: The expression can be simplified into 7 - 3, and when you subtract a number, you go left on the number line, so the point 3 left of 7
Part B: 7 - 3 = 4, and to get to 0 from 4, you need to subtract 4 or add -4

We have two points:

The point slope form of the line:

Substitute


Answer:

Add the 3 ratio portions together: 1 + 4 + 7 = 12
Divide total length by 12:
84/12 = 7
Multiply each ratio portion by 7:
1 x 7 = 7
4 x 7 = 28
7 x 7 = 49
The longest piece is 49 cm