Answer:
Step-by-step explanation:
x-y=7
-3x+9y=-39
Divide the second equation by 3
-x +3y = -13
Add this to the first equation
x-y=7
-x +3y = -13
----------------------
0x +2y = -6
Divide by 2
2y/2 = -6/2
y = -3
Now find x
x-y = 7
x -(-3) = 7
x+3 = 7
Subtract 3 from each side
x = 4
(4,-3)
Or by substitution
x-y=7
solve for x
x = 7+y
-3x+9y=-39
Substitute y+7 in for x
-3(7+y) +9y = -39
Distribute
-21 -3y +9y = -39
Combine like terms
-21 +6y = -39
Add 21 to each side
6y = -18
Answer:
13.82 in.
Step-by-step explanation:
To find the circumference of a circle, you multiply the diameter by pi (
):
Rounded to the nearest tenth, 13.82301 is 13.82. Therefore, 13.82 is the answer.
I hope this helps!
Answer:
(x, y) = (2, -1.5)
Step-by-step explanation:
x + 2y = -1
5x - 4y = 16
<=>
(2)x + (2)2y = (2)(-1)
5x - 4y = 16
<=>
2x + 4y = -2
5x - 4y = 16
<=>
7x = 14
<=>
x = 2
(*)x + 2y = -1
=> 2 + 2y = -1
=> 2y = -3
=> y = -1.5
=> (x, y) = (2, -1.5)
Answer:
r=4
Step-by-step explanation:
15r-6r=36
9r=36
r=36/9
r=4
Adjacent angles-
2 angles that share a common vertex, a common side and no common interior points.
The answer is ADJACENT ANGLE
