Help
Toggle navigation
System Homepage
Grades 7 & 8 Mathematics
Equations and the Pythagorean Theorem (A)
Lesson 14: Equations with Multiple Variables
Watch
Try This
Try This Problem Revisited
Using Trial and Error
Using a Combination of Trial and Error and Algebra
Applications of Multiple Variables in Geometry
Alternative Format
Review
Question 1
Question 2
Question 3
Question 4
Practise
Exercises
Answers and Solutions
Question Descriptions
Exercises
Consider the equation \(P=2x+2y\). If \(x=4\) and \(y=9\), find the value of \(P\).
The equation \(V=5n+25q\) describes the total value, \(V\), of \(n\) nickels and \(q\) quarters.
If you have \(4\) nickels and \(7\) quarters in your hand, what is your total amount?
If \(V=200\), then \(200=5n+25q\). Find one solution to the equation.
Show that there is more than one solution to the equation \(200=5n+25q\).
Amusement park admission prices are listed as:
Adult: \($48\)
Student: \($30\)
Child under 10: \($24\)
Write an equation to represent the total cost, \(T\), for a family of \(a\) adults, \(s\) students, and \(c\) children.
If a group spent \($150\) on admissions to the amusement park, how many adults, students, and children might have gone?
\(100\) can be written as the sum of two numbers, one of which is a multiple of \(2\) and the other a multiple of \(3\). Find two numbers that fit this description.
Explain how your solution from part a) gives you a solution to the equation \(100=2x+3y\).
Exactly \(120\) tickets were sold for a concert. The tickets cost \($12\) each for adults, \($10\) each for seniors, and \($6\) each for children. The number of adult tickets sold was equal to the number of child tickets sold. Given that the total revenue from the ticket sales was \($1100\), how many senior tickets were sold?
One soccer ball and one soccer jersey together cost \($100\). They each cost a whole dollar amount.
Write an equation to represent this problem.
Describe the possible costs for the soccer ball and soccer jersey.
A dodecahedron is a convex polygon with \(12\) pentagonal faces. How many edges and vertices does a dodecahedron have?
A game starts with the integer \(0\) and produces a sequence of integers. On each turn, you may perform one of the following four operations on the current number to produce the next number in the sequence:
Add \(5\)
Subtract \(5\)
Add \(17\)
Subtract \(17\)
Therefore, the first term in the sequence is \(0\) and the second term will be \(5\), \(-5\), \(17\), or \(-17\), depending on what operation is performed on \(0\). Here is an example of the beginning of one possible sequence in this game:\[0 \xrightarrow{+17} 17 \xrightarrow{-5} 12 \rightarrow \ldots\] In this game, is it possible to produce a sequence that contains the number \(1\)? If so, explain how.
Previous
More
Quit
Previous Unit Item
Next Unit Item
Next