Answer:
A) 8x + 9y = −3
B) 6x + 7y = 1
We multiply A) by -(6/8)
A) -6x -6.75y = 2.25 then we add this to equation B
B) 6x + 7y = 1
.25y = 3.25
y = 13
and x = -15
Step-by-step explanation:
<span>First, calculate the difference between 15 and 12. The operation, subtraction, will give us the answer of 3. Then, divide the calculated value by 12 since this it the theoretical length of the nail. Multiply the quotient by 100% to arrive to the final answer. That is (3/12)(100%). The final answer to this item is 25% which is the last choice. </span>
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:
All positive integers
Step-by-step explanation:
Notice how it’s on pure positive quarter of the 4 quarters.