Solve fx gx What are the points of intersection of the grap
Solution
Equating \"
-3x^2 + 6 = 4x + 7
3x^2 + 4x + 1 = 0
Now, this is a quadratic of the form ax^2 + bx + c
which can be factored(sometimes, but here it can be factored).
a = 3, b= 4 and c = 1
Now, we need two numbers that sum to b
Sum = 4
And those numbers multiply to ac
Multiply to 3(1) = 3
Sum = 4 and product = 3
This happens with the numbers 3 and 1...
So, we have :
3x^2 + 3x + x + 1
3x(x + 1) + 1(x + 1) = 0
(3x + 1)(x + 1) =0
3x + 1 = 0 and x + 1= 0
x = -1/3 and x =-1
x = -1 , -1/3
Now, when x = -1 y = -4 + 7 = 3
When x = -1/3, y = -4/3 + 7 = 17/3
So, answers :
x = -1 , -1/3
(-1 , 3) , (-1/3 , 17/3)
