All GMAT Math Resources
Example Questions
Example Question #2 : Graphing A Two Step Inequality
Which of the following inequalities is graphed above?
None of the above.
In order to graph the inequality pictured above, we must first find the equation of its boundary line. Based on the image, we see that the line includes the points and , so the slope of the line is
.
We can now find the -intercept form of the line by substituting and the point into the slope-intercept equation and solving for :
The equation of the boundary line is therefore . Since we see that the boundary line is dashed, we know that the values on the line are excluded from the inequality, so the sign will be replaced by a or a .
In order to determine which one, we can test a point in the solution set; let's test since it's the simplest to substitute:
_____
_____
_____
, so the correct symbol is :
Example Question #3 : Graphing A Two Step Inequality
Which of the following inequalities is graphed above?
None of the above.
In order to graph the inequality pictured above, we must first find the equation of its boundary line. Based on the image, we see that the line includes the points and , so the slope of the line is
.
We can now find the -intercept form of the line by substituting and the point into the slope-intercept equation and solving for :
The equation of the boundary line is therefore . Since we see that the boundary line is solid, we know that the values on the line are included in the inequality, so the sign will be replaced by a or a .
In order to determine which one, we can test a point in the solution set; let's test :
_____
_____
_____
, so the correct symbol is :
Example Question #4 : Graphing A Two Step Inequality
Which of the following inequalities is graphed above?
None of the above.
In order to graph the inequality pictured above, we must first find the equation of its boundary line. Based on the image, we see that the line includes the points and , so the slope of the line is
.
We can now find the -intercept form of the line by substituting and the point into the slope-intercept equation and solving for :
The equation of the boundary line is therefore . Since we see that the boundary line is dashed, we know that the values on the line are excluded from the inequality, so the sign will be replaced by a or a .
In order to determine which one, we can test a point in the solution set; let's test :
_____
_____
_____
, so the correct symbol is :
Example Question #1 : Algebra
Which equation is linear?
none of them are linear
Let's go through all of the answer choices.
1. : and are both constants, so the equation is actually linear.
2. 5x + 7y - 8yz = 16: This is not linear because of the yz term.
3. : This can be transformed into y + 8 = (x + 6)(x - 2). Clearly when this is expanded, there will be an term, so this is not linear.
4. : This is not linear either, also because of the term.
Example Question #2 : Algebra
Solve.
Solve for in the first equation:
Substitute into the second equation:
Solve for .
Example Question #3 : Algebra
What is
Solve the first equation to get
Substitute that into the second equation and get
Solve the equation to get , then substitute that into the first equation to get .
Plugging those two values into , gives
Example Question #2 : Algebra
Solve the system of equations:
The system has no solution.
The system has no solution.
Multiply both sides of the first equation by 12:
Now, add both sides of the two equations:
Since this is impossible, the system of equations is inconsistent and thus has no solution.
Example Question #4 : Algebra
Give the solution set for .
Insufficient information is given to answer the question.
The expression on the left factors as the difference of squares:
Since , we can substitute:
We now have a system of linear equations to solve:
Example Question #1 : Algebra
A company wants to ship some widgets. If the weight of the box plus one widget is 6 pounds, and the weight of the box plus two widgets is 10 pounds, then what is the weight of the box and the weight of the widget? Put the answer in an ordered pair such that the ordered pair is (box weight, widget weight).
Let the weight of the box be represented by and the weight of the widget be represented by . Since the weight of the box plus the weight of one widget is 6 pounds, this can be represented by the equation
Since the weight of the box plus two widgets is 10 pounds, this can be represented by the equation
We now have two equations and two unknowns and we can now solve for and . To do this we solve the first equation for and substitute it into the second equation. Solving the first equation for we get
Substituting this into the second equation we get
Using and substituting it into the first equation we get
So the weight of the box is 2 pounds and the weight of the widget is 4 pounds. This gives us the ordered pair .
Example Question #5 : Algebra
Solve for when
Plug in the given value and then isolate .