How do you solve #2x^2-x=3# by graphing?

1 Answer
Lucy
May 5, 2018

#(3/2, 3) and (-1,3)#

Explanation:

First you graph the equation #y=2x^2-x#

graph{2x^2-x [-10, 10, -5, 5]}

Then you graph the equation #y=3# onto the same graph. Hopefully, you will notice that the graphs meet at two different points. Those two points are the answer to your equation.

To make sure, you can also solve the equation by graphing.

#2x^2-x=3#
#2x^2-x-3=0#
#(2x-3)(x+1)=0#

#2x-3=0# or #x+1=0#
#x=3/2 or -1#

Therefore, your two points are #(3/2, 3) and (-1,3)#

Related questions
See all questions in Quadratic Functions and Their Graphs
Impact of this question
1795 views around the world
You can reuse this answer
Creative Commons License