Open Up - Grade 8 - Mathematics - Unit 4 - Lesson 7

Last updated 9 months ago
12 questions
1

For each equation, decide if it is always true or never true.

  • x-13=x+1
  • x+\frac{1}{2}=x-\frac{1}{2}
  • x-3=2x-3-x
  • 2(x+3)=5x+6-3x
  • 3(x-5)=2(x-5)+x
  • True
  • Never True
1

Mai says that the equation 2x+2=x+1 has no solution because the left hand side is double the right hand side.

Do you agree with Mai?

1

Write the other side of this equation so it's true for all values of x:\frac{1}{2}(6x-10)-x=

1

Write the other side of this equation so it's true for no values of x:\frac{1}{2}(6x-10)-x=

1

Here is an equation that is true for all values of x:5(x+2)=5x+10 . Elena saw this equation and says she can tell 20(x+2)+31=4(5x+10) is also true for any value of x. How can she tell?

Explain your reasoning.

1

Elena and Lin are trying to solve \frac{1}{2}+3=\frac{7}{2}x+5 . Describe the change they each make to each side of the equation.
  1. Elena’s first step is to write 3=\frac{7}{2}-{1}{2}x+5.

1

Elena and Lin are trying to solve \frac{1}{2}+3=\frac{7}{2}x+5 . Describe the change they each make to each side of the equation.
  1. Elena’s first step is to write x+6=7x+10.

1

Solve each equation and check your solution.(If your answer is a fraction, keep it as a fraction.)

3x-6=4(2-3x)-8x

1

Solve each equation and check your solution.(If your answer is a fraction, keep it as a fraction.)

\frac{1}{2}z+6=\frac{3}{2}(z+6)

1

Solve each equation and check your solution.(If your answer is a fraction, keep it as a fraction.)

9-7w=8w+8

1

The point (-3,6) is on a line with a slope of 4.

Find two more points on the line.

1

The point is on a line with a slope of 4.

Write an equation for the line.

"Source: Open Up Resouces (Download for free at openupresources.org.)"