Answer:
Step-by-step explanation:
Let x and y represent the cost of a cookie and a cupcake, respectively.
4x +3y = 13.25
5x +2y = 11.75 . . . . . . the system of equations
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By Cramer's rule:
x = (3(11.75) -2(13.25))/(3(5) -2(4)) = 8.75/7 = 1.25
y = (13.25(5) -11.75(4))/7 = 19.25/7 = 2.75
The cost of one cookie is $1.25; the cost of one cupcake is $2.75.
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Cramer's rule gives the solution to the system of equations ...
ax +by =c
dx +ey = f
as ...
∆ = bd -ea
x = (bf -ec)/∆
y = (cd -fa)/∆
Answer:
D. 3
Step-by-step explanation:
Assuming the model represents an equation, the following can be deduced:
On the left side of the equation, the model shows we have 3 "x's", and 6 "1's". Let this represent:
3x + 6
On the right side of the equation, we have 2 "x's" and 9 "1's". Let this represent:
2x + 9.
The model would represent the equation below:
Solve for x
(Subtracting 2x from both sides of the equation)
(subtracting 6 from both sides of the equation)