69.0k views
4 votes
How many x-intercepts does the graph of y = 2x2 + 4x - 3 have?

2 Answers

5 votes

Answer:

3

Explanation:

Given

y

=

2

x

2

4

x

+

3

The y-intercept is the value of

y

when

x

=

0

XXX

y

=

2

(

0

)

2

4

(

0

)

+

3

=

3

For a quadratic in the general form:

XXX

y

=

a

x

2

+

b

x

+

c

the determinant

Δ

=

b

2

4

a

c

indicates the number of zeros.

Δ

<

0

==⇒

no solutions

=

0

==⇒

one solution

>

0

==⇒

two solutions

In this case

XXX

Δ

=

(

4

)

2

4

(

2

)

(

3

)

<

0

so there are no solutions (i.e. no values for which the expression is equal to zero).

This can also be seen from a graph of this equation:

graph{2x^2-4x+3 [-6.66, 13.34, -0.64, 9.36]}

Answer link

Vinícius Ferraz

Nov 13, 2015

(

0

,

3

)

Explanation:

x

=

0

y

=

0

0

+

3

y

=

0

x

=

b

±

b

2

4

a

c

2

a

a

=

2

,

b

=

4

,

c

=

3

But

Δ

< 0, then there is no real root

(

x

0

,

0

)

.

User Jacob Gabrielson
by
4.9k points
2 votes

Answer:

it has 2

Explanation:

I hope this helps!

User Aayushi
by
5.2k points