We first multiply the second equation by 4.

So our resulting equation is:

Then we subtract the first equation from the second new equation.

Left Hand Side:

Right Hand Side:

Resulting Equation:

We divide both sides by -15

Left Hand Side:

Right Hand Side:

Our result is:

Let s equal the cost of the shirt and p equal to the cost of a pair of pants. The question can be set up as follows:

The top equation can be multiplied by 4 to give:

The bottom equation can be subtracted from the top equation to give:

Dividing by 5 gives the cost of a pair of pants:

This can be plugged into either one of the initial equations to solve for the cost of the shirt.

Subtracting both sides by 96 gives:

The question asks for the cost of a pair of pants and a shirt which is the sume of the costs. 

Solve for  or  first.  Let's solve for .  To do this, we must eliminate the  variables.  Multiply the first equation by the coefficient of the  variable in the second equation.

Subtract the second equation from the first equation and solve for .

Resubstitute this value to either original equations.  Let's substitute this value into .

Find the common denominator and solve for the unknown variable.

The correct answer is:  

If  then adding  is equal to . If  then  or .  This means that  is equal to  or .

We can solve this system of equations by elimination. 

By adding the second equation to the first, we get  or .

Substitute y=-4 into either equation and solve for x. 

Simplify and solve for x to get .

Therefore, the solution to this system of equations as an ordered pair is (7, -4). 

We can express this problem as a system of equations where s represents scones and d represents donuts. 

We can solve this system of equations by elimination as follows:

Subtracting the second equation from the first yields  or . 

Therefore, donuts cost $2. 

We can express the given information as a system of equations. Let L represent the votes cast for Lisa, and let J represent the votes cast for Jon. 

The total votes cast in the election can be written as

Since Lisa received 50 more votes than Jon, we can write

We can solve this system of equations by substitution.

Let's rewrite the second equation in terms of J. 

.

Now, we can substitute  into .

This gives us

We can simplify this to get .

To calculate the percentage of the votes that were cast for Lisa, we take her 150 votes and divide them by the total number of votes cast in the election. Then, we multiply that by 100%.

0.6 x 100% = 60%

Any time the product of consecutive numbers is , must be a one of those consecutive numbers, because if it is not, the product will be non-zero. This leaves us with four possibilities, depending on where  is placed in the sequence.

As we can see, , , and are our numbers in question, meaning is our answer as the lowest number.

Note that it is possible to use algebra and set up a system of equations, but it's more time-consuming, which could hinder more than help in a standardized test setting.

If we use elimination to solve this system of equations, we can add the two equations together. This results in 0=0. 

When elimination results in 0=0, that means that the two equations represent the same line. Therefore, there are an infinite number of solutions. 

We can solve this system of equations by elimination since the 2 given y-values have the same coefficient. Let's subtract the second equation from the first.

This gives us  or .

Substitute this x-value into either equation and solve for y. Let's use the first equation like so:

The solution is .