So firstly, we have to find the LCD, or lowest common denominator, of 9 and 7. To do this, list the multiples of 9 and 7 and the lowest multiple they share is going to be your LCD. In this case, the LCD of 9 and 7 is 63. Multiply x^2/9 by 7/7 and 2y/7 by 9/9:

Next, add the numerators together, and your answer will be: 
9 and 10
11 and 12
13 and 14
15 and 16
the square root of 125 is 11.18 so therefore it falls between 11 and 12
A minus before a parenthesis means we need to change the sign.
So 2 + 8 - 3 = 7
There are a few ways to solve this. The method I will use is the substitution method. Since they give us a "y = " statement, we can replace the y in the second equation with what it gives us to the right of the equal sign.
- 3x + 6(- 2x - 1) = 24
Simplify by using the distributive property.
- 3x + 6(- 2x) + 6(- 1) = 24
- 3x - 12x - 6 = 24.
Combine like terms
- 15x - 6 = 24
Add 6 to each side.
- 15x = 30
Divide both sides by - 15 to isolate variable X
x = 30 / - 15
x = - 2.
Now plug in the x-value we've found back into the first equation.
y = - 2( - 2) - 1
y = 4 - 1
y = 3
Your answer is (- 2, 3)
Line:
3x+y=7
y=-3x+7
Slope of Perpendicular Line: 1/3x
For the perpendicular line to contain point (6,-1) the y-intercept would be (0,1), thus the equation of the line would be y=1/3x+1
y=1/3x+1