9 + x = 17
17 - 9 = x
x = 8
Answer:
Amount of vinegar. 100% : 20 milliliters
Amount of Italian dressing: 140 milliliters
Step-by-step explanation:
Let's call A the amount of vinegar. 100%
Let's call B the amount of Italian dressing . 12% vinegar
The resulting mixture should have 23% vinegar, and 160 milliliters.
Then we know that the total amount of mixture will be:
Then the total amount of pure antifreeze in the mixture will be:
Then we have two equations and two unknowns so we solve the system of equations. Multiply the first equation by -1 and add it to the second equation:
+
--------------------------------------
We substitute the value of B into one of the two equations and solve for A.
Answer:
The temperature needs to decrease 71° - 50° = 21° that at least not greater than 50°F
As we know, the device decrease the temperature down 3.5° every hour, so
21 : 3.5 = 6 hour
Call x is the hours we need to wait to let the device decrease, we have
x > 6
Answer d because the y intercept is 3 and its a positive slope
Answer:
The cost of each:
1 cheese slice = c = $3.75
1 pepperoni slice = p = $2.5
Step-by-step explanation:
Let the cost:
1 cheese slice = c
1 pepperoni slice = p
Two friends are going to the mall to buy pizza.
One of the friends buys 1cheese slice and 2 pepperoni slices for $8.75.
c + 2p = $8.75.....Equation 1
c = $8.75 - 2p
Her friend purchases 2 chese slices and 3 pepperoni slices for $15.00.
2c + 3p = $15.00.....Equation 2
We substitute 8.75 - 2p for c in Equation 2
2(8.75 - 2p) + 3p = $15.00
17.5 - 4p + 3p = 15
Collect like terms
- 4p + 3p = 15 - 17.5
-p = -2.5
p = $2.5
c = $8.75 - 2p
c = $8.75 - 2(2.5)
c = $8.75 - 5.0
c = $3.75
The cost of each:
1 cheese slice = c = $3.75
1 pepperoni slice = p = $2.5
