Graphing
The intersection of two lines is called the __________ of a system of equations.
A. Perpendicular
B. Parallel
C. Solution
solution
What must be true in order to perform substitution for a system of equations?
A. Both equations must be in standard form
B. Both equations must be in slope form
C. One of the equations must be set equal to either x or y.
C. One of the equations must be set equal to either x or y.
What is the purpose of elimanation for a system of equations? in other words what are we eliminating?
We are eliminating one of the variables to solve for the other variable
The sum of two numbers is 20 and their difference is 10. What are those two numbers?
15 and 5
If two lines are parallel then they have________
A. No solution
B. One solution
C. Infinite solutions
No solution
What is the first step in substitution?
solve one equation for x or y
In order to eliminate one variable what must be true about the coefficients?
A. The coefficients must be the same
B. The coefficients must be reciprocals
C. The coefficients must be one
A. The coefficients must be the same.
For word problems, the two linear equations will typically take on a particular form. What is that form called?
A. Slope formula
B. Slope intercept form
C. Standard form
D. point slope form
C. Standard form
If two lines lie on top of each other then they have _________
A. No solution
B. One solution
C. Infinite solutions
Infinite solutions
After you solve for a variable during substitution what is the next step?
plug the value of that variable into either equation to solve for the second variable.
What is the first step in solving system of equations with elimination?
Make sure the equations are lined up
David bought 3 DVDs for 4 books for $40 at a yard sale. Anna bought 1 DVD and 6 books for $18. How much did each DVD and book cost?
12 dollars for a DVD 1 dollar for a book
y = x - 1 and x + 4y = 16
find the solution
(4,3)
2x - 5y = -22 and x + 7y = 27
find the solution using substitution.
( -1, 4)
y = -x + 1 and y = 4x - 14
(3, -2)
Airline fares for a flight from Dallas to Austin are $30 for first class and $25 for tourist class. If a flight had 52 passengers who paid $1360, how many first class and tourist class passengers were there?
12 first class and 40 tourist class
2x + y = 8 and x = 5
find the solution
(5, -2)
y = -3x - 13 and 9x - 2y = -4
find the solution using substitution
(-2,-7)
x - 2y = 10 and x + 3y = 5
find the solution using elimination
(8, -1)
Sue has 100 coins consisting of dimes and quarters. If the total value of the coins is $21.40, how many of each kind of coin does she have?
24 dimes and 76 quarters