How do you find the x and y intercepts for y=3x2?

2 Answers

y=2
x=0
(0,2)

Explanation:

Add two to both sides.
y=3x2
to
y+2=3x

Next, instead of x, put y+2.
y+2=3(y+2)

Then, multiply 3 by y and 3 by 2.
y+2=3y+6

Subtract y from both sides.
2+y=3y+6
to
2=2y+6

Subtract 6 from both sides.
2=2y+6
to
4=2y

Divide both sides by 2.
4=2y
to
2=y
Go back to the original equation. Replace y with 2.
y=3x2
to
2=3x2

Add 2 to both sides.
2=3x2
to
0=3x

Divide both sides by 3.
0=3x
to
0=x

Hope that helped! : )

Apr 12, 2018

The x-intercept is (23,0).

The y-intercept is (0,2).

Explanation:

Given:

y=3x2

X-intercept: value of x when y=0.

Substitute 0 for y.

0=3x2

Add 2 to both sides.

2=3x

Divide both sides by 3.

23=x

The x-intercept is (23,0).

Y-intercept: value of y when x=0

y=3x2 is the slope-intercept form for a linear equation:

y=mx+b,

where:

m is the slope, and b is the y-intercept.

Therefore, the y-intercept is (0,2).

You can also substitute 2 for x and solve for y.

y=3(0)2

y=2

The y-intercept is (0,2).

graph{y=3x-2 [-10, 10, -5, 5]}