Answer:
20 is my answer and the question is somehow confusing
Answer:
Cuanto dinero voy a pagar 24 $
Cuanto recibiré de cambio 76 $
Step-by-step explanation:
Mis compras son:
1 lápiz 3,50 $
2 plumas 7,90 $
1Libreta 12,60 $
Lo que quiere decir que compre:
3,50 + 7,90 + 12,60 = 24 $
Si cancelo mis compras con un billete de 100 $ me tienen que dar vuelto por:
100 $ - 24 $ = 76 $
To solve for x in terms of b, simply treat b as a number, and solve for x as usual: first of all, we expand the left hand side:

Subtract 10 from both sides:

Divide both sides by -2b:

This means that in particular, if we set
, we have

1/5(x-y) = 1
x+y = 9
x-y = 5 (x5)
x+y = 9
First you want to create both equations so at least one of the variables (x or y) are the same in both equations, so that is why I multiplied the top one by 5, you multiply the whole equation (both sides)
2x = 14
x = 7
Then you either Plus or minus one from the other, I plused the top one onto the bottom one, then solved for x
7 + y = 9
y = 2
Then put x back into one of the first two equations to get Y
<em>Note: I am assuming your second equation is:</em>
<em>x = 2y - 1</em>
<em></em>
Answer:
The solution to the system of equations is:
Step-by-step explanation:
Given the system of equations
2x+y=3
x = 2y - 1
solving the system of equations using the elimination method

Arrange equation variables for elimination

Multiply x-2y=-1 by2: 2x-4y=-2

subtracting the equations




now solve -5y = -5 for y

Divide both sides by -5

Simplify

For 2x+y=3 plug in y=1

subtract 1 from both sides

Simplify

Divide both sides by 2

Simplify

Therefore, the solution to the system of equations is: