Pls help thank you. Find the value of the expression use estimation to check your answer

2.) 2703

4.) 9

Step-by-step explanation:

2.)

5327 - 2624 = ?

We subtract from left to right to get;

(7 - 4 = 3) then (2 - 2 = 0) then carrying  1 from 5, (13 - 6 = 7) and (4 - 2 = 2)

So writing the answer;

2 then 7 then 0 then 3

i.e Answer = 2703

4.)

648 ÷ 72 = ?

72 × 10 = 720

So we must multiply 72 by a number less than 10 since 720 > 648

We should look for a number such that 2 in 72 times the number should give an answer with 8 in the end.

Such a number can be 9;

Manually multiplying 72 and 9 we get 648 and we are right!

x² + 11x + 18 < 0  

[-11 ± sqrt(121 - 72)]/2 = (-11 ± 7)/2  

solution: (-9, -2)

step-by-step explanation:

1

x = 1

step-by-step explanation:

0 ÷ x = 0

0 ÷ 1 = 0