Answer:
9/16
Step-by-step explanation:
i got it right on khan academy
Since drapes have to be covered all over the window and the beneath of the window, both lengths have to be added.
(2 2/3) + ( 2 3/4)
(8/3) + (11/4)
(32+33)/12
65/12
5 5/12
There are many ways to do this. Such ways are using the quadratic formula, completing the square, etc.
We have
![x^2+10x-21=0](https://tex.z-dn.net/?f=x%5E2%2B10x-21%3D0)
We can add 46 to both sides so the -21 becomes a +25. by doing that, we get
![x^2+10x+25=46](https://tex.z-dn.net/?f=x%5E2%2B10x%2B25%3D46)
This can be wrote as
![(x+5)^2=46](https://tex.z-dn.net/?f=%28x%2B5%29%5E2%3D46)
We solve the square root and get
![(x+5)= +-\sqrt{46}](https://tex.z-dn.net/?f=%28x%2B5%29%3D%20%2B-%5Csqrt%7B46%7D%20)
(The +- is a plus minus sign.) Subtract five on both sides to get
![x=-5+- \sqrt{46}](https://tex.z-dn.net/?f=x%3D-5%2B-%20%5Csqrt%7B46%7D%20)
The answer is
C.
Answer:
Step-by-step explanation:
3x+8y=-5
-2x+2y=18
Ok, so you want to get either x or y to cancel out so lets multiply the first equation by 2 and the second equation by 3.
6x+16y=-10
-6x+6y=54
Now x can cancel out. The new equation is:
22y=44
y=2
Now you input 2 into one of the original problems.
-2x+2(2)=18
-2x+4=18
Now subtract 4 from both sides.
-2x=14
Divide
x=-7
Now check your answer.
-2(-7)+2(2)=18
14+4=18