Using front-end estimation, find a reasonable estimate of:

21,000

Step-by-step explanation:

front end estimation requires you to take the front / first digit of each number in this expression and round.

if you don't know how to round, basically you take the next digit after the first one, (in 719 you take the 1) and determine if that's below or above 5. If below, then keep the original first number. If above, add one more to the first digit. If the number is five itself, it is most common to round up (so add one).

like 425 would round to just 400; and 676 would round to 700.

multiply  700 and 30

youd get 21000

correct answer is infinitely many solutions

step-by-step explanation:

2(2x + 3) = -4 + 2(2x + 5)

solving the above equation:

4x + 6 = -4 +4x +10

combining like terms

4x -4x = -4+10-6

0=0

since both sides are 0=0, we end up into true statement it means it has infinite many solutions.

so correct answer is infinitely many solutions