What are the solutions to the system of equations? x2 + y2 = 5 y = 2x.
2 answers:
Answer:
(1, 2) and (- 1, - 2)
Step-by-step explanation:
Given the 2 equations
x² + y² = 5 → (1)
y = 2x → (2)
Substitute y = 2x into (1)
x² + (2x)² = 5, that is
x² + 4x² = 5
5x² = 5 ( divide both sides by 5 )
x² = 1 ( take the square root of both sides )
x = ± = ± 1
Substitute these values into (2) for corresponding values of y
x = 1 → y = 2(1) = 2 ⇒ (1, 2)
x = - 1 → y = 2(- 1) = - 2 ⇒ (- 1, - 2)
You might be interested in
Answer:
the parabola can be written as:
f(x) = y = a*x^2 + b*x + c
first step.
find the vertex at:
x = -b/2a
the vertex will be the point (-b/2a, f(-b/2a))
now, if a is positive, then the arms of the parabola go up, if a is negative, the arms of the parabola go down.
The next step is to see if we have real roots by using the Bhaskara's equation:
Now, draw the vertex, after that draw the values of the roots in the x-axis, and now conect the points with the general draw of the parabola.
If you do not have any real roots, you can feed into the parabola some different values of x around the vertex
for example at:
x = (-b/2a) + 1 and x = (-b/2a) - 1
those two values should give the same value of y, and now you can connect the vertex with those two points.
If you want a more exact drawing, you can add more points (like x = (-b/2a) + 3 and x = (-b/2a) - 3) and connect them, as more points you add, the best sketch you will have.