E Your Turn
5 of
Bernard received $205 in cash and $245 in
ripe to
checks as graduation presents. He decided to
ecided open a bank account with that money. Each
2
week he will add $45 from his weekly paycheck
- The
to the account. Write an equation that can be
used to determine the total amount of money,
of the
m, Bernard has in the account after w weeks.
an
tion?

Aspacecraft can attain a stable orbit 300 kilometers above earth if it reaches a velocity of 7.7 kilometers per second. the formula for a rocket's maximum velocity v in kilometers per second is vequalsminus0.0098tplusc ln upper r, where t is the firing time in seconds, c is the velocity of the exhaust in kilometers per second, and r is the ratio of the mass of the rocket filled with fuel to the mass of the rocket without fuel. find the velocity of a spacecraft whose booster rocket has a mass ratio of 20, an exhaust velocity of 2.1 km/s, and a firing time of 15 s. can the spacecraft achieve a stable orbit 300 km above earth?