7.7m is more precise because it has a decimal after it
$36
I think
$0.89 rounds up to $1.00
$0.75 rounds up to $1.00
$1.60 rounds up to $2.00
then multiply each by 9 for the 9 children
9
9
18
then add together
9+9+18=36
Answer: -300 meters
Step-by-step explanation: If he started from 0 (sea level) and went 300 meters under, meaning 0-300=-300 meters.
To factor quadratic equations of the form ax^2+bx+c=y, you must find two values, j and k, which satisfy two conditions.
jk=ac and j+k=b
The you replace the single linear term bx with jx and kx. Finally then you factor the first pair of terms and the second pair of terms. In this problem...
2k^2-5k-18=0
2k^2+4k-9k-18=0
2k(k+2)-9(k+2)=0
(2k-9)(k+2)=0
so k=-2 and 9/2
k=(-2, 4.5)