Name: ________________________________ Date: _______________________ Hour: _________
Lesson 8.2 – Solving Systems by Substitution
Solve each system by substitution. Check your answer.
1.)
y  3x

y  x  4
2.)
3 x  y  25

y  x  3
3.)
y  4 x

y  2x  6
4.)
y  x  2

2 x  y  4
5.)
y  4  x

y  4  1 x
6.)
y  x  2

y  4 x  1
7.)
2 x  y  6

 x  y  3
8.)
3 x  y  2

4 x  y  20
9.)
 x  y  3

 x  y  1
y  4 x  1
10.) 
4 x   y  1
 x  2y  0
11.) 
3 x  5 y  11
3 x  2y  7
12.) 
 x  3y  5
Write a system of equations for the situation and use it to answer the following questions.
13.) A professional organizer charges a $45 consultation fee, plus $20 per hour.
Her competitor charges a $30 consultation fee, plus $26 per hour.
a.)
Write a system of equations to represent the situation.
b.)
Solve the system by substitution. For what number of hours will the total charge be the
same?
c.)
What will that charge be?
14.) A jar contains n nickels and d dimes. There are 20 coins in the jar, and the total
value of the coins is $1.40. (Hint: Nickels are worth $0.05 and dimes are worth
$0.10.)
a.)
Write a system of equations to represent the situation.
b.)
Solve the system by substitution. How many nickels and how many dimes are in the jar?