Substitution
y = 3x + 1
y = 6x + 10
x = -3 , y = -8
4x + 9y = 29
6x - 9y = 21
x = 5, y = 1
x + 5y = 13
x + y = -3
x = -7, y = 4
- 14x - 6y = 14
7x + 5y = 7
x = -4, y= 7
1 ruler and 2 pens cost $1.50
3 pens cost $1.20
How much does a ruler cost?
$0.70
y = -2x + 13
y = 4x - 11
x = 4, y = 5
2x - 2y = -18
5x + 2y = -24
x = -6, y = 3
x + 4y = 26
x = 6, y = 5
9x - 7y = 23
18x + 9y = 0
x = 1, y = -2
3 chocolate bars and 2 lolly bags cost a total of $8.50
1 chocolate bar and 4 lolly bags cost a total of $7
How much does each cost separately?
Chocolate bar = $2
Lolly Bag = $1.25
4x + 2y = -20
y = x - 4
x = -2, y = -6
-8x - 5y = 18
8x + 7y = -22
x = -1, y = -2
-5x - 6y = 14
3x - 6y = -18
x = -4, y = 1
x - 2y = -7
3x - 4y = -15
x = -1, y = 3
Two numbers have a sum of 20 and a difference of 8. What are the numbers?
14 and 6
5x - y = 21
y = -7x + 15
x = 3, y = -6
5x - 4y = -8
-5x + 6y = 12
x = 0, y = 2
-8x + 2y = 28
-8x - 7y = 10
x = -3, y = 2
-x + 3y = -15
7x + 6y = -3
x = 3, y = -4
Five years ago, I was 5 times older than my son. In 8 years' time I will be 3 times older than my son. How old am I today?
70 years old
y = -8x - 3
8x + 4y = 12
x = -1, y = 5
4x - 5y = 7
-8x + 5y = 1
x = -2, y = -3
-2x - 4y = 8
-5x - 4y = -10
x = 6, y = -5
-8x + 12y = 16
-6x - 6y = -18
x = 1, y = 2
Mayfield High School sold tickets for a school musical. Seats in the auditorium cost $6 each and balcony seats cost $4. A total of 200 tickets was sold and $960 was collected. How many of each type of ticket was sold?
120 Balcony Seats
80 Auditorium Seats