1. ©G Dear 2010 – Not to be sold/Free to use
Applied Mathematic
(Preliminary General 1)
Algebra
Harder
Substitution
Stage 6 - Year 11
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©G Dear 2010 – Not to be sold/Free to use

2. Algebraic Substitution - Simple
Replacing pronumerals with numbers.
The formula for the speed of a car is
v = u + a t
Problem: The Porche 911 does a rolling start. Initial speed is 2.8 m/s [approx 10 km/h] and acceleration is 8 m/s2. How long will it take to reach 28 m/s [approx 100 km/h]?
v = u + at
-2.8
-2.8
28 =
2.8
+ 8
x t ÷8 ÷8
25.2 = 8
x t
t = 3.2 seconds

3. Algebraic Substitution - Simple
Replacing pronumerals with numbers.
The formula for the simple interest is
I = P r n
Problem: The Porche 911 costs $ The interest rate is 8% (0.08). The interest paid was $ How long was the car loan taken for?
I = P r n =
x 0.08
x n
÷14000
÷14000
= 14000
x n
n = 6 years