Answer:
c. 4x + 20 = 140
Step-by-step explanation:
Perimeter = 140 feet
Width = L + 10
P = 2w + 2L
P = 2(L + 10) + 2L
P = 2L + 20 + 2L
P = 4L + 20
Answer:
Russell family's sprinkler: 40 hours
Gonzales family's sprinkler: 20 hours
Step-by-step explanation:
Let's call the amount of time the Russell family's sprinkler was on by X, and the Gonzales family's sprinkler by Y.
We can then formulate the equations:
X + Y = 60
X*35 + Y*40 = 2200
We can solve this system multiplying the first equation by 35, and then subtracting the result from the second equation:
35*X + 35*Y = 2100
5*Y = 100
Y = 20
from the first equation:
X + 20 = 60
X = 40
Russell family's sprinkler: 40 hours
Gonzales family's sprinkler: 20 hours
2 1/4 + 1 2/4 ≠ 5
Why?
2 1/4 + 1 2/4
=3 3/4
The answer is wrong because the student added wrong. The real answer is 3 3/4.
Answer: -2 4/15
Step-by-step explanation: To properly subtract, we need to find a common denominator. We can list the multiples of 3 and 5 to find the common denominator:
3: 3, 6, 9, 12, 15
5: 5, 10, 15
The first common multiple we see is 15.
Calculation:
3 · 3 = 9
9 + 1 = 10
3 1/3 = 10/3
5 x 5 = 25
25 + 3 = 28
-5 3/5 = -28/5
Now to convert into fifteen as the denominator:
-28/5 = -28 x 3/5 x 3 = -84/15
10/3 = 10 x 5/3 x 5 = 50/15
Now to subtract accordingly:
50/15 - 84/15 = -34/15
Final answer: -34/15 (can be reduced to -2 4/15).
Answer:
Step-by-step explanation: