There has to be more to this question then i can help you
First we have to isolate the varible
-2/5x-2=18
+2 +2
-2/5x=20
then divide both sides by -2/5 to get x completely by itself
-2/5x=20
------- ---
-2/5 -2/5
x=-50
i hope i've helped!
x3[x+4y=1]
-
3x+5y=10
-1y=-9
x-1 [-1y=-9]
y=9
Answer:
19338 kWh
Step-by-step explanation:
In Arizona, electricity cost eleven cents per kilowatt-hour.
The average home uses 66 million BTU per year i.e. 66000000 BTU per year.
Now, it is given in the question that 1 BTU is equivalent to 0.000293 kWh.
So, the average home uses (66000000 × 0.000293) = 19338 kWh per year.
Therefore, the number of kilowatt-hours used per year will be 19338. (Answer)
Answer:
11
Step-by-step explanation:
1.80m + 0.6s = 12.00
[substitute the value of m into the equation]
1.80×(3) + 0.6s = 12
5.4 + 0.6s = 12
[make s the subject of the formula]
0.6s = 12 - 5.4
0.6s = 6.6
[divide both sides of the equation by 0.6]
0.6s / 0.6 = 6.6 / 0.6
s = 11
To prove that 11 is correct
[substitute the value of m and s into the equation]
1.80m + 0.6m = 12.00
1.80×(3) + 0.6×(11) = 12.00
5.4 + 6.6 = 12.00
12.00 = 12.00