Step-by-step explanation:
- 3x+5y=7b equation 1
- 2x+4y=1
2x=-4y+1
- x=(-4y+1)/2
- x=(-4y+1)/2 in equation 1
3×(-4y+1)/2+5y=7b
(-12y+3)/2+5y=7b
(-12y+3+10y)/2=7b
(-12y+3)/2=7b
-12y+3=14b
-12y=14b-3
- y=3-14b/12
- y=3-14b/12 in x=(-4y+1)/2
x=(-4×{3-14b/12}+1)/2
x=(-3+14b)/3+1/2
x=14b/3×1/2
Answer:
2. Judy =$5
Ben= $4
Step-by-step explanation:
2. Let Judy = x and Ben = y
8x + 10y = 80
9x + 5y = 65
Solve these simultaneous equations.
8
x + 10
y = 80
18
x + 10
y = 130
Take the second equation away from the first equation
−
10
x = −
50
x = 5
This means that Judy gets paid $5 an hour.
Therefore, Ben gets paid $4 an hour.
Answer:
3. 24 quarters and 16 dimes
Step-by-step explanation:
3. Let the number of dimes = x and the number of quarters = y
Value Value
Type Number of of
of of EACH ALL
coin coins coin coins
-------------------------------------------
dimes x $0.10 $0.10x
quarters y $0.25 $0.25y
-------------------------------------------
TOTALS 40 $7.60
x + y = 40
0.10x + 0.25y = 7.60
Get rid of decimals by multiplying every term by 100:
10x + 25y = 760
So we have the system of equations:
x + y = 40
10x + 25y = 760
We solve by substitution. Solve the first equation for y:
x + y = 40
y = 40 - x
Substitute (40 - x) for y in 10x + 25y = 760
10x + 25(40 - x) = 760
10x + 1000 - 25x = 760
-15x + 1000 = 760
-15x = -240
x = 16 = the number of dimes.
Substitute in y = 40 - x
y = 40 - (16)
y = 24 quarters.
$1.60 + $6.00 = $7.60
I hope that helped, sorry for taking so long :-)
X is equal to 8
Y is equal to 0
creo que paco es el mayor. lo siento si me equivoco! no soy muy buena en las proporciones
