Answer:
Fried crab cakes = $4.50
Cup of gumbo = $3.25
Step-by-step explanation:
Let's make the price of fried crab cakes = x and the price of a cup of gumbo = y. Set up two equations for x and y and solve for each variable.
<h3><u>Setting up the equations:</u></h3>
4 people ordered x and 4 people ordered y for a total of 31 dollars, so this equation would look like: 4x + 4y = 31
2 people ordered x and 1 person ordered y for a total of $12.25, so this equation would look like: 2x + y = 12.25
<h3><u>Substitution method:</u></h3>
Now you have your two equations-- solve for a variable in one of the equations and substitute that value into the other equation.
The easiest way to start would be to solve for y in the second equation by subtracting 2x from both sides.
y = 12.25 - 2x
Substitute this value into the first equation.
4x + 4(12.25 - 2x) = 31
Now solve for x-- start by distributing 4 inside the parentheses.
4x + (49 - 8x) = 31
Combine like terms.
-4x + 49 = 31
Subtract 49 from both sides.
-4x = -18
Divide both sides by -4.
x = 4.5
Substitute this value of x into our starting equation for which we solved for y.
2(4.5) + y = 12.25
Multiply 2 and 4.5 together.
9 + y = 12.25
Subtract 9 from both sides.
y = 3.25
Each order of fried crab cakes is worth the x-value [$4.50] and each cup of gumbo is worth the y-value [$3.25].
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