Question

Solve the following system of equations and show all work.

y = −x2 + 4
y = 2x + 1

Answer 1

@Preetha

Answer 2

@ganeshie8

Answer 3

I know the answers i just need help with how to get there

Answer 4

@Hero

Answer 5

@Shalante any ideas??

Answer 6

\[x^2\] is x^2 not x2

Answer 7

yes, sorry it copy and pasted wrong

Answer 8

if y=-x^2+4
and y=2x+1
then -x^2+4=2x+1
Know how to solve for x?

Answer 9

not really lol

Answer 10

if you do know how to solve for x, plug the x value to any of the equation to get y

Answer 11

we don't know the x value

Answer 12

\[-x^2+4=2x+1\]

Answer 13

so solve and that is the solution?

Answer 14

\[x^2+2x-3\]
move it over

Answer 15

yes you know how to solve that?

Answer 16

there should be two solutions with both having (x,y) form

Answer 17

what is the first step to solve that? lost again

Answer 18

where do i go after the x^2+2x-3

Answer 19

factor it ( )( )

Answer 20

(x-1) (x+3) ?
sorry I'm confused

Answer 21

?

Answer 22

Yea you are right.

Answer 23

then what?

Answer 24

oops

Answer 25

dunno why it took me back to my old reply

Answer 26

forgot to tell you its
\[x^2+2x-3=0\]

Answer 27

so quadratic ?

Answer 28

that is what happens when you move all the numbers to the other side of an equation. After everything is gone, you a zero to it.

Answer 29

yes i know

Answer 30

so you get -3 after solving

Answer 31

and 1

Answer 32

so those are the x's what about the y's??

Answer 33

Then plug both this x back into the first 2 equation using both x=-3 and x=1

Answer 34

they should both equal right?

Answer 35

yes they both get -5

Answer 36

ANSWER #1 (x,y) plug in first x
ANSWER #2 (x,y) plug in second x

Answer 37

oops my orignial was wrong hold on

Answer 38

so answer #1 is (-3,-5). you are correct on first one.

Answer 39

I got everything under control! thanks so much!

Answer 40

Yea, no problem.