Substitution in Solving Linear Equations

Unit 5 Systems of Linear Equations

Section 2

Algebra

Mrs. LaGrange

Solving a system of linear equations by substitution involves three steps.

Multiple Choice

ax+r=7

solve for r

• r=7/ax

• r=7-ax

• r=7+ax

• r=7ax

Multiple Choice

Which expression represents the value of x in the equation:

dx + e = f

• x = (f + e)/d

• x = (f - e)/d

• x = d/(e - f)

• x = d/(e + f)

Multiple Choice

IR = V

(solve for R)

• R = IV

• R = ^I/_V

• R = ^V/_I

• R = V - I

Multiple Choice

Solve for y:

8x + 4y= 16

• y = -8x + 16

• y = 2x -4

• y = -2x + 4

• y = -8x + 12

Multiple Choice

If y=4,find the value of 3y+5

• 27

• 12

• 17

Multiple Choice

If x=5,find the value of 7x-1

• 34

• 36

• 35

Multiple Choice

What is the solution to this system?

x - y = 6

y = 2x - 5

• (1,3)

• (-1,3)

• (-1,-7)

• (1,-7)

Multiple Choice

y = -2x + 18

y = 8

• (5, 8)

• (-5, 8)

• (2, 8)

• (-2, 8)

Multiple Choice

Solve this system of equations.

y = 2x + 1

y = 4x - 1

• (1,3)

• (-1,-3)

• (-1,3)

• (3,1)

Great job!

Your assignment for today is IXL Algebra S12 up to 50 points for full credit, and U8 strive for 85 points for full credit. See classroom post for more details.

Formative Value:

S12 5 points

U8 10 points

Total 15 Formative Points.