System of Equations Algebraically

Solve:
y = 2x -11
-3y = -6x -15

• (-1.5,-4)

• (1.5,4)

• No solution (parallel lines)

• Infinitely many solutions

4x+8y=20
-4x+2y=-30

• (-7,1)

• (2,-5)

• (-2,5)

• (7,-1)

Solve the system of Equation (x,y)
x + 4y = –3
 x + 7y = –12 

• (-3,9)

• (9,-3)

• (3,9)

• (9,3)

Solve the system of Equation (x,y)
3x + y = –21
x + y = –5  

• (-3,8)

• (8,-3)

• (3,-8)

• (-8,3)

Solve this system using elimination
4x+ 9y = 28
-4x -y = -28

• (-7,0)

• (6,0)

• (-6,0)

• (7,0)

Solve for x and y
5x + 3y = 7
y = 4

• (4,1)

• (4,-1)

• (1,4)

• (-1,4)

x-y=11
2x+y=19

• (10,-1)

• (-1,10)

• (3,-4)

• (6,7)

2x - y = 0

4x - y = 0

• (1,2)

• (0,0)

• No Solutions

• Infinite Solutions

Is (3,-4) a solution to this system?

• yes

• no

Which answer has a correct first step for solving this system without graphing:

• The variable is already isolated, so we've already solved the system.

• The variable is already isolated for y, so we substitute it in the first equation and solve for x

  3x + 3(3x + 5) = 3

• Free sha vaca doo

• The variable is already isolated for y, so we substitute it in the second equation and solve for x

  y = 3(3x + 3y) = 3

Answer explanation

$3x+3y=3$

$y=3x+5$
A variable is already isolated here, so we already have an equivalent expression from the second equation that can be substituted in place of y in the first equation.