Solving Quadratics by Substitution - PowerPoint PPT Presentation

1 / 4
About This Presentation
Title:

Solving Quadratics by Substitution

Description:

Solving Quadratics by Substitution Solve for x or y ... Solve the Quadratic by factoring.(In this problem you can ... Problems Assignment #1 Solving ... – PowerPoint PPT presentation

Number of Views:132
Avg rating:3.0/5.0
Slides: 5
Provided by: NISD160
Category:

less

Transcript and Presenter's Notes

Title: Solving Quadratics by Substitution


1
Solving Quadratics by Substitution
y2 x 6 0 x y 0
Solve for x or y Plug in the expression for y.
y -x (-x)2 x 6 0 x2 x 6 0 (x
2)(x 3) 0 x -2 x 3
Simplify and combine like terms
Solve the Quadratic by factoring.(If you cant
factor use quadratic formula or completing the
square)
y - (-2) y -(3) y 2
y -3
Plug your answers back into one of the original
problems.
(-2,2) (3,-3)
Solutions are point of intersection.
2
Solving Quadratics by Substitution
y x2 2x 3 y -x2 2x 3
Solve for x or y Since they are both already y
you can set them to each other.
x2 2x 3 -x2 2x 3 2x2 4x 6 0 x2
2x - 3 0 (x 1)(x 3) 0 x 1 x -3
Simplify and combine like terms
Solve the Quadratic by factoring.(In this problem
you can divivide by 2 first)
Plug your answers back into one of the original
problems.
y 12 2(1) 3 y (-3)2 2(-3) 3 y
1 2 - 3 y 9 6 3 y 0
y 0
Solutions are point of intersection.
(1,0) (-3,0)
3
Solving Quadratics by Substitution
x2 6x 4y 3 0 y 3x 1 0
Solve for x or y Plug in the expression for y.
Simplify and combine like terms
Solve the Quadratic by factoring.(If you cant
factor use quadratic formula or completing the
square)
Plug your answers back into one of the original
problems.
Solutions are point of intersection.
4
Practice Problems
Write a Comment
User Comments (0)
About PowerShow.com