Write a system of equations to describe the situation below, solve using an augmented matrix, and fill in the blanks.McCoy's Bakery sold one customer 1 dozen chocolate cookies for $7. The bakery also sold another customer 4 dozen chocolate cookies and 8 dozen oatmeal cookies for $76. How much do the cookies cost?A dozen chocolate cookies cost $_____, and a dozen oatmeal cookies cost $_____.
Q. Write a system of equations to describe the situation below, solve using an augmented matrix, and fill in the blanks.McCoy's Bakery sold one customer 1 dozen chocolate cookies for $7. The bakery also sold another customer 4 dozen chocolate cookies and 8 dozen oatmeal cookies for $76. How much do the cookies cost?A dozen chocolate cookies cost $_____, and a dozen oatmeal cookies cost $_____.
Define Variables: Let x be the cost per dozen of chocolate cookies and y be the cost per dozen of oatmeal cookies.For the first customer: 1 dozen chocolate cookies = $7.Equation: 1x+0y=7
First Customer Equation: For the second customer: 4 dozen chocolate cookies and 8 dozen oatmeal cookies = $76. Equation: 4x+8y=76
Second Customer Equation: Create an augmented matrix to represent the system of equations:\begin{array}{cc|c}
1 & 0 & 7 \
4 & 8 & 76
\end{array}
Create Augmented Matrix: Use row operations to find the reduced row echelon form.First, multiply the first row by −4 and add it to the second row to eliminate the x-term in the second equation.−4×∣∣1amp;07amp;∣∣+∣∣4amp;876amp;∣∣=∣∣4amp;876amp;∣∣+∣∣−4amp;0−28amp;∣∣=∣∣0amp;848amp;∣∣
Reduce to Echelon Form: Now we have the new system of equations represented by the matrix:(1amp;0amp;∣amp;70amp;8amp;∣amp;48)
Solve for y: Divide the second row by 8 to solve for y.0amp;8amp;∣amp;48 / 8 = 0amp;1amp;∣amp;6Now we have y=6.
Solve for x: Substitute y=6 into the first equation to solve for x.1x+0(6)=7x=7
Final Cost Solution: We have found that x=7 and y=6. A dozen chocolate cookies cost $7, and a dozen oatmeal cookies cost $6.
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