184,000 can be rounded by underlining the 3 in the thousands place and look to the right. if, it is more than 5 add 1 to the left, 184.... then replace the numbers behind the rounded number, will be 0. 184,000
<span />
I dont know if this is right but the answer to 2(12+8x)-3(4x-9) might be 4x+51?