Answer:
x=1, y=2
Step-by-step explanation:
x + 7y = 15
x + 2y = 5
Subtract the two equations
x + 7y = 15
-x - 2y =- 5
------------------------
0x +5y = 10
Divide by 5
5y/5 = 10/5
y =2
Now find x
x+2y = 5
x +2(2) = 5
x +4 = 5
Subtract 4 from each side
x-4+4 = 5-4
x = 1
1. Rewrite the system:
x+12y=68 (i)
x=8y-12 (ii)
2. Let's substitute the equation (ii) into the equation (i):
x+12y=68
(8y-12)+12y=68
3. Then, you have:
8y-12+12y=68
4. When you clear "y", you have:
20y-12=68
20y=68+12
20y=80
y=80/20
y=4
5. You already have the value of "y". Now, you must substitute this value into the equation (ii):
x=8y-12
x=8(4)-12
x=32-12
x=20
6. Therefore, the result is:
x=20
y=4
Answer:
A. 40°C B. -10°C per kilometer
Step-by-step explanation:
As the height increase, the temperature decreases.
Answer:
radius=11.5
diameter=23
Step-by-step explanation:
The volume of a sphere is V=4/3 Pi r^3
We can use this to solve for the radius.
555.4= 4/3 (3.14)r^3
Solve for r how you would any other equation. Multiply 4/3 and 3.14.
555.4=4.187 r^3
Divide both sides by 4.187
132.65=r^3
To get rid of the ^3, find the cube root of both sides on a calcualtor.
r= 11.5
The diameter is the radius time two.
11.5 (2)=23.
Hope this helps!
Note: When I say both sides, I mean both sides of the = sign.
