All ACT Math Resources
Example Questions
Example Question #511 : Algebra
Solve and . What is the sum of and ?
Adding the two equations together gives , so . Substituting into one of the original equations gives
The sum of and is
Example Question #242 : Equations / Inequalities
Suppose x2 + x – 6 = 0. Which of the following could be a value of x?
0
2
3
1
4
2
Factor out this binomial. –3 and 2 are the only possible x values. 2 is the answer.
Example Question #243 : Equations / Inequalities
Find a solution for the following system of equations:
x – y = 2
2x – 3y = 3
(1, 3)
(3, 0)
(3, 1)
(0, 0)
(0, 1)
(3, 1)
Use substitution and solve for one variable, then back substitute and solve for the other variable, or use elimination.
Example Question #26 : Systems Of Equations
Solve the following system of equations:
There are two ways to solve this problem.
Option 1: The Substitution Method
Step 1: Set up the second equation so that is by itself
Step 2: Substitute for in the first equation, and solve for
Step 3: Plug into the second equation and solve for
Option 2: The Elimination Method
Step 1: Set up the equations so that the variables are on the same side
Step 2: Multiple the second equation by 2
Step 3: Subtract the second equation from the first (thereby canceling out the s) and solve for x
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Step 4: Substitute into one of the equations and solve for
Example Question #2014 : Act Math
Solve for and .
Setting both equations equal to gives
and
Setting these expressions equal to each other gives
So, .
Plugging that back into the first equation:
The final answer is and .
Example Question #2 : Inequalities
Solve for .
For the second equation, solve for in terms of .
Plug this value of y into the first equation.
Example Question #2 : Evaluating Expressions
A store sells 17 coffee mugs for $169. Some of the mugs are $12 each and some are $7 each. How many $7 coffee mugs were sold?
6
7
8
10
9
7
The answer is 7.
Write two independent equations that represent the problem.
x + y = 17 and 12x + 7y = 169
If we solve the first equation for x, we get x = 17 – y and we can plug this into the second equation.
12(17 – y) + 7y = 169
204 – 12y + 7y =169
–5y = –35
y = 7
Example Question #1 : How To Find The Solution For A System Of Equations
What is the solution of for the systems of equations?
We add the two systems of equations:
For the Left Hand Side:
For the Right Hand Side:
So our resulting equation is:
Divide both sides by 10:
For the Left Hand Side:
For the Right Hand Side:
Our result is:
Example Question #2 : How To Find The Solution For A System Of Equations
What is the solution of that satisfies both equations?
Reduce the second system by dividing by 3.
Second Equation:
We this by 3.
Then we subtract the first equation from our new equation.
First Equation:
First Equation - Second Equation:
Left Hand Side:
Right Hand Side:
Our result is:
Example Question #2 : Creating Equations With Whole Numbers
What is the solution of for the two systems of equations?
We first add both systems of equations.
Left Hand Side:
Right Hand Side:
Our resulting equation is:
We divide both sides by 3.
Left Hand Side:
Right Hand Side:
Our resulting equation is: