Answer:
Different ways to solve a system of linear equations:
- isolate one variable in one equation and replace it in the other equation
- multiply/divide one equation by a constant and then add/subtract it to the other one, so that only one variable remains
- graph the equation and look at the intersection point
If you graph the system:
- there is only one solution if the lines intersects at only one point
- there is no solution if the lines don't intersect each other (they are parallel)
- there are infinitely many solutions if the lines overlap each other (they are the same equation multiplied by some constant)
Step-by-step explanation:
1st system
y = -x – 7
y = 4/3 x – 7
solution: x= 0, y = 7
2nd system
y = -3x – 5
y = x + 3
solution: x = -2, y = 1
3rd system
y = -2x + 5
y = 1/3 x – 2
solution: x = 3, y = -1
4th system
3x + 2y = 2
x + 2y = -2
solution: x = 2, y = -2
5th system
x + 3y = -9
2x – y = -4
solution: x = -3, y = -2
6th system
x – 2y = 2
-x + 4y = -8
solution: x = -4, y = -3
7th system
5x + y = -2
x + y = 2
solution: x = -1, y = -3
Answer:
8
Step-by-step explanation:
Number x Square x2 Cube x3
2 4 8
Answer:
28
Step-by-step explanation:
Since B is the midpoint of AC, that means AB = BC. That means 3x+4 = 5x-6. We can now set up an equation to solve for x:
3x+4 = 5x-6
3x+10 = 5x
10 = 2x
x = 5
Now that we know what x is, we can just plug x into the expression of AB and multiply it by 2:
(3*(5)+4)*2
=(15+4)*2
=19*2
=28
(side note: we could have plugged x into the expression of BC as well, but in this case plugging it into AB tends to be easier to solve)
Therefore, the length of AC is 28.