Answer and Step-by-step explanation:
The signs didn't really "swap". Instead, the whole function was divided by -1, or we could say the function was divided by -3. That would turn:
-18x² - 15x + 3 = 0
into
(-18 / -3)x² - (15 / -3)x + (3 / -3) = 0
6x² + 5x - 1 = 0
And that gives the "swapped signs".
Answer:
Eq: (x+a/2)²+(y+1)²=(a²-8)/4
Center: O(-a/2, -1)
Radius: r=0.5×sqrt(a²-8)
Mandatory: a>2×sqrt(2)
Step-by-step explanation:
The circle with center in O(xo,yo) and radius r has the equation:
(x-xo)²+(y-yo)²=r²
We have:
x²+y²+ax+2y+3=0
But: x²+ax=x²+2(a/2)x+a²/4-a²/4= (x+a/2)²-a²/4
And
y²+2y+3=y²+2y+1+2=(y+1)²+2
Replacing, we get:
(x+a/2)²-a²/4+(y+1)²+2=0
(x+a/2)²+(y+1)²=a²/4-2=(a²-8)/4
By visual inspection we note that:
- center of circle: O(-a/2, -1)
- radius: r=sqrt((a²-8)/4)=0.5×sqrt(a²-8). This means a²>8 or a>2×sqrt(2)
Answer:
50kg
Step-by-step explanation:
K = Keith B = Beth H = Henry
K = 20 + B
H = 2B - 30
K = H
20 + B = 2B - 30
B = 50kg
Answer:
B.less cakes
Step-by-step explanation:
If she keeps making 20 cakes she will lose profit.
If she makes more she will lose profit.
She has to make less cakes to stop losing profits.
So the answer is B. Make less Cakes
Answer:
2.75, and - 2.75
Step-by-step explanation:
Both have an absolute value of 2.75 which is how far away they are from 0.
Hope this helped!