129k views
3 votes
Use the intersect method to solve the equation -2x+1=-x^2+4

A) x=-1, 3
B) x=1, -3
C )x=1
D) x=4

2 Answers

5 votes

Answer:

a

Explanation:

x=-1,3

User Qimolin
by
8.6k points
4 votes
-2x+1=-x^2+4

X^2 - 2X + 1 - 4 =0

X^2-2X-3=0

discriminant= (-2)^2 - 4(-3)(1)
=16

D1 = {-(-2)+√16}/2

D1=(2+4)/2
=6/2

D1=3.

D2={-(-2)-√16}/2
=(2-4)/2
=-2/2

D2= -1


the solutions are {-1 ; 3 }
so A) x= -1,3
User Bigskull
by
7.8k points