Posted by **Tom** on Friday, November 9, 2012 at 1:50pm.

help me solve this equation by substitution.

y^2− 4x^2 = 7

9y^2+16x^2 = 323

- Algebra -
**Reiny**, Friday, November 9, 2012 at 3:33pm
from the 1st: y^2 = 4x^2 + 7

into the 2nd

9(4x^2 + 7) + 16x^2 = 323

36x^2 + 63 + 16y^2 = 323

52y^2 = 260

y^2 = 5

y = ± √5

sub y^2 = 5 into the 1st:

5 - 4x^2 = 7

-4x^2 = -2

x^2 = 1/2

x = ± 1/√2

4 solutions:

x=√5, y= 1/√2

x = -√5, y = 1/√2

x = √5, y = -1/√2

x = -√5 , y = -1/√2

your graph would show an ellipse intersecting with a hyperbola, with 4 symmetric points of intersection

## Answer This Question

## Related Questions

- Algebra - I just cannot seem to get these two problems. Any help is greatly ...
- algebra - Solve the system by addition or substitution. 16x-4y=20 y=4x-4 I ask ...
- Algebra - There are two solutions to | 16x - 5 | = 3. The greatest solution is ...
- Pre Calculus - Determine two coterminal angles (one positive and one negative) ...
- Mathematics - Determine two coterminal angles (one positive and one negative) ...
- algebra - The equation f(x) = 4x2 − 16x + 9 represents a parabola. What is...
- algebra 1 - solve by substitution. 0.5x+0.25y=36 y+18=16x
- math - Solve the following equation. 16x^2 − 16x + 4 = 0 x = 1 (smaller ...
- Math - PreCalc (12th Grade) - Which rectangular equation corresponds to these ...
- calculus - i need to find the derivative using chain rule: (x^2 + 2x - 6)^2 (1-x...

More Related Questions