Answer:
- cookie: $1.25
- cupcake: $2.75
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)/∆
-(7x + 4)- 2x + 2 = 52
Distribute the negative sign:
-7x -4 - 2x + 2 = 52
Combine like terms:
-9x - 2 = 52
Add 2 to both sides:
-9x = 54
Divide by -9:
x = -6
Answer: x = -6
Answer:
Solve by substitution
[y=5/2x-4]
[y= -x+3]
Substitute y = -x +3
[-x+3=5/2x-4]
Isolate x for -x+3=5/2x-4: x=2
For y = -x+3
Substitute x = 2
y= -2+3
Simplify
y=1
The solutions to the system of equations are:
y=1 x=2
Answer:
4.166666.... which is equal to 25/6
Step-by-step explanation: