Question

How many solutions are there for the system shown below?
x^2 + 4y^2 = 100
4y - x^2 = - 20

A. 4
B. 3 <-- I think it has 3...?
C. 1
D. 2

Answer 1

can u plz show your work?

Answer 2

4y - x^2 = -20
4 * (-5) - x^2 = -20
-20 - x^2 = -20
0 = x^2
x = 0

I had help for this one ... i had a hard time with it

4y^2 + x^2 + 4y - x^2 = 100 - 20
4y^2 + 4y = 80
y^2 + y = 20
y^2 + y - 20 = 0
y = (-1 +/- sqrt(1 + 80)) / 2
y = (-1 +/- 9) / 2
y = -10/2 , 8/2
y = -5 , 4


4 * 4 - x^2 = -20
16 - x^2 = -20
36 = x^2
x = -6 , 6

Answer 3

It has three

Answer 4

Quite Right...:)

Answer 5

sweet thanks!!!

Answer 6

yw........:)