Answer:
C
Step-by-step explanation:
Under a reflection in the y- axis
a point (x, y ) → (- x, y ), thus
A(3, 4 ) → A'(- 3, 4 )
Since the point A and it's reflection lie on a horizontal line then
distance between = | 3 + 3 | = | 6 | = 6
Write the equation 11x-24+3x-20=180. The answer is 16.
X+Y=10
XY=-300
Solve for one of the variables
X=10-Y
Plug into the other equation
Y(10-Y)=-300
Now, you have a quadratic...
-y²-10y+300=0
I would multiply everything by -1, so there's no coefficient on y²
y²+10y-300=0
And solve...
-10±√(100-4(-300))
----------------------------
2
Y=-5±5√(13)
Plug back onto original equation...
X+(-5±5√(13))=10
X±5√(13)=15
X=15±5√(13)
Note: There are 2 sets of answers, keep the negatives with the negatives, and the positives with the positives when dealing with the ±.
B=c-5
c+b=185
so, c+(c-5)=185
2c=190
c=95
b=90
As simple as that.
Y=210-7X you have $210 and want to know how many books she can buy with that money.