414,125 views
29 votes
29 votes
Solve the system of equations:
y = 2x - 4
y= x^2 - 4

User Ola Berntsson
by
2.8k points

1 Answer

17 votes
17 votes

Answer:

correct question


\\ \longmapsto y=2x -4


\\ \longmapstoy=x²-4

________________________

The two intersections would be (3, 10) and (-2, 0)

Explanation:

To solve this system of equations, set the two equations equal to each other and solve for x.


\\ \mapsto2x + 4 = x² + x - 2


\\ \mapsto2x = x² + x - 6


\\ \mapsto0 = x² - x - 6


\\ \mapsto0 = (x - 3)(x + 2)

Now set the parenthesis equal to zero to get the x values.


\\ \mapstox - 3 = 0


\\ \mapstox = 3


\\ \mapstox + 2 = 0


\\ \longmapstox = -2

Now we know the x values of each interception. We can find the y values by plugging into either equation.


\\ \mapstoy = 2x + 4


\\ \mapstoy = 2(3) + 4


\\ \mapstoy = 6 + 4


\\ \longmapstoy = 10


\\ \mapstoy = 2x + 4


\\ \mapstoy = 2(-2) + 4


\\ \mapstoy = -4 + 4


\\ \longmapstoy = 0

User Lee Harold
by
2.8k points