-x+4y + z = 10
x+2y + 3z = 4
2x-3y + 2z = -7

What is the value of x in the this question ?

Sam opened a money-market account that pays 3% simple interest. he started the account with $7,000 and made no further deposits. when he closed the account, he had earned $420 in interest. how long did he keep his account open?

Darren earned $663.26 in net pay for working 38 hours. he paid $118.51 in federal and state income taxes, and $64.75 in fica taxes. what was darren's hourly wage? question options: $17.45 $19.16 $20.57 $22.28