9a)
4x - 2 + 30 = 68
4x + 28 = 68
4x = 40
x = 10
9b)
y = 180 -68
y= 112
The best estimate for 1,374 is 1,400 and the best estimate for 6 is 10. This is because anything that is 5 and above you change it. Example: 16 the best estimate for 16 is 20 because 6 is above 5. And when a number is 4 and below you change the number below. Example: 12 the best estimate for 12 is 10 because 2 is below 4. And when the number is perfect like 10, you can keep the number the same. Example:10,20,30,40,50,60etc.
Hope this Helped! :)
Answer:
looks like D! Have a nice day :D