Answer:
n = -33
Step-by-step explanation:
Let n = number
Sum of a number and 9
(n+9)
is tripled
3(n+9)
the result is six less then twice the number
2n-6
3(n+9) = 2n-6
Distribute
3n+27 = 2n-6
Subtract 2n from each side
3n-2n +27 = -6
n +27 = -6
Subtract 27 from each side
n+27-27 = -6-27
n =-33
3y - 1 = 28
+ 1 + 1
----------------
3y = 29
---- ----
3 3
y= 9.66
Kim's Loan:
Let A = amount borrowed from bank A.
Let B = amount borrowed from bank B.
The total loan is $55,000.
Therefore
A + B = 55000 (1)
Bank A charges 8% interest. The interest after 1 year is 0.08A.
Bank B charges 11% interest. The interest after 1 year is 0.11B.
Total interest after 1 year is $5,000.
Therefore
0.08A + 0.11B = 5000 (2)
From (1), obtain
B = 55000 - A (3)
Substitute (3) into (2).
0.08A + 0.11(55000 - A) = 5000
0.08A + 6050 - 0.11A = 5000
-0.03A = -1050
A = -1050/-0.03 = 35000
Answer: Kim borrowed $35,000 from bank A.
Jack's Loan.
A = loan from bank A.
B = loan from bank B.
The total loan is $10,000.
Therefore
A + B = 10000 (4)
Bank A charges 5% interest and bank B charges 6% interest.
Total interest after 1 year is $530, therefore
0.05A + 0.06B = 530 (5)
From (4), obtain
B = 10000 - A (6)
Substitute (6) into (5).
0.05A + 0.06(10000 - A) = 530
0.05A + 600 - 0.06A = 530
-0.01A = -70
A = -70/-0.01 = 7000
Answer: Jack borrowed $7,000 from bank A.