Tips For Success

Read the question below. Then follow the tips to answer the sample question.

Tip 1

Find where y = 0 . y equals 0 .  These are the x-intercepts of the graph.

Tip 2

Check your solutions in the original equation.

The graph below shows the quadratic function y = 2 x 2 + 2 x − 4 . y equals , 2 x squared , plus 2 x minus 4 .  Use the graph to find the solutions of 2 x 2 + 2 x − 4 = 0 . 2 x squared , plus 2 x minus 4 equals 0 .

1. − 4  and  0 negative 4 , and , 0
2. − 2  and  1 negative 2 , and , 1
3. − 1  and  2 negative 1 , and , 2
4. 2  and − 1 2 , and , minus 1

Think It Through

The x-intercepts of the graph are at x = − 2 x equals negative 2  and x = 1 . x equals 1 .

Substitute to verify your answers.

2 ( − 2 ) 2 + 2 ( − 2 ) − 4 = 2 ( 4 ) − 4 − 4 = 0 2 ( 1 ) 2 + 2 ( 1 ) − 4 = 2 + 2 − 4 = 0 table with 6 rows and 1 column , row1 column 1 , 2 . open negative 2 close squared . plus 2 open negative 2 close minus 4 , row2 column 1 , equals 2 open 4 close , negative 4 , minus 4 , row3 column 1 , equals 0 , row4 column 1 , 2 . open 1 close squared . plus 2 open 1 close minus 4 , row5 column 1 , equals , 2 plus 2 , minus 4 , row6 column 1 , equals 0 , end table

The correct answer is B.