Page 104 - Algebra 1

SOLUTION
P7-1 or P6
P7-1 or P6 = $1450
P7 = 1.04(P7-1)
P7 = 1.04(1450)
P7 = $1508
P8 = 1.04(P8-1)
P8-1 or P7
P8 = 1.04(1508)
P8 = $1568.32
Her principal balance is $1568.32 after 8 years.
Caution
In the equation
Py = 1.04(Py-1), the subscript y refers to a particular number of years. So, y - 1 refers to 1 year less than y.
represents the principal balance after 6 years
Write the formula for the principal balance after 7 years. Substitute 1450 for P7-1.
Write the formula for the principal balance after 8 years. represents the principal balance after 7 years Substitute 1508 for P8-1.
Lesson Practice
Evaluate each expression for the given values of the variables.
ax[-a(a - x)] for a = 2 and x = -1
-b[-b(b - c) - (c - b)] for b = -2 and c = 0
a.
(Ex 1)
b.
(Ex 1)
c.
(Ex 2)
d.
(Ex 2)
Simplify each expression. Then evaluate for a = 2 and b = -1. Justify each step. (Ex 3)
e. -b(a - 3) + a
f. -a(-b - a) - b
(5y)(2z)4xy for x = 3, y = -1, and z = _1 _2
4rs for r = -1, s = -3, and t = -2 6st
Evaluate each expression for the given values of th_e variable.
(Ex 4)
g. If a = -2 and b = 25, what is the value of _ b
-b(a - 4) + b h. If x = -4 and y = -2, what is the value of x2 - x⎪y⎥ ?
?
x3
i. A savings account grows according to the formula Py = 1.04(Py-1), where
(Ex 5) Py is the principal balance at the end of y years and Py-1 is the principal balance after y - 1 years. After 6 years, there is a principal balance of $1600.00. How much is the principal balance after 8 years?
Lesson 16 89