SAT Math : How to find x or y intercept

Study concepts, example questions & explanations for SAT Math

varsity tutors app store varsity tutors android store varsity tutors amazon store varsity tutors ibooks store

Example Questions

Example Question #11 : How To Find X Or Y Intercept

At what point does the graph 3y-2x=31 cross the -axis?

Possible Answers:

Correct answer:

Explanation:

The graph crosses the -axis where x=0. So plugging in and solving yields \frac{31}{3}

Example Question #12 : How To Find X Or Y Intercept

Find the x-intercepts of  25x^{2}+4y^{2} = 9.

Possible Answers:

5

2

\pm \frac{3}{5}

\frac{3}{5}

\pm 5

Correct answer:

\pm \frac{3}{5}

Explanation:

To find the x-intercepts, plug y=0 into the equation and solve for x.

25x^{2} + 4\cdot 0^{2} = 9

25x^{2} = 9

x^{2} = \frac{9}{25}

x = \pm \frac{3}{5}

Don't forget that there are two solutions, both negative and positive!

Example Question #211 : Coordinate Geometry

A line with the exquation y=x^2+3x+c passes through the point .  What is the -intercept?

Possible Answers:

Correct answer:

Explanation:

By plugging in the coordinate, we can figure out that .  The -Intercept is when , plugging in 0 for gives us .

Example Question #11 : How To Find X Or Y Intercept

What are the -intercept(s) of the following line:

Possible Answers:

Correct answer:

Explanation:

We can factor and set  equal to zero to determine the -intercepts.

satisfies this equation.

 

Therefore our -intercepts are  and .

Example Question #212 : Coordinate Geometry

Which of the following lines does not intersect the line ?

Possible Answers:

Correct answer:

Explanation:

Parallel lines never intersect, so you are looking for a line that has the same slope as the one given. The slope of the given line is –4, and the slope of the line in y = –4x + 5 is –4 as well. Since these two lines have equal slopes, they will run parallel and can never intersect.

Example Question #11 : How To Find X Or Y Intercept

Find the y-intercept of .

Possible Answers:

12

3

14

5

7

Correct answer:

7

Explanation:

To find the y-intercept, set x equal to zero and solve for y.

This gives y = 3(0)2 + 2(0) +7 = 7.

Example Question #13 : How To Find X Or Y Intercept

The slope of a line is m=\frac{4}{3}. The line passes through (2,7). What is the x-intercept?

Possible Answers:

(0,9\frac{2}{3})

None of the available answers

(0,4.3)

(4\frac{1}{3},0)

Correct answer:

Explanation:

The equation for a line is:

y=mx+b, or in this case

y=\frac{4}{3}x+b

We can solve for b by plugging in the values given

7=\frac{4}{3}\times 2+b

7=2\frac{2}{3}+b

b=7-2\frac{2}{3}=4\frac{1}{3}

Our line is now

y=\frac{4}{3}x+4\frac{1}{3}

Our x-intercept occurs when \dpi{100} y=0, so plugging in and solving for \dpi{100} x:

\dpi{100} 0=\frac{4}{3}x+4\frac{1}{3}

\dpi{100} -\frac{13}{3}=\frac{4}{3}x

\dpi{100} x=-\frac{13}{4}

Example Question #215 : Coordinate Geometry

Determine the x-intercept for the equation:  

Possible Answers:

Correct answer:

Explanation:

The x-intercept is the x-value when the value of .  Substitute this value and solve for .

The x-intercept is .

Example Question #11 : How To Find X Or Y Intercept

What is the y intercept of 

Possible Answers:

The line does not cross the y axis.

y=12

y=-3

y=3

Correct answer:

y=3

Explanation:

To find the y intercept, substitute x=0

Example Question #216 : Coordinate Geometry

At what point does the line  intersect the y-axis?

Possible Answers:

None of the given answers

Correct answer:

Explanation:

We know that in slope-intercept form, , that  represents the y-intercept. So, let's rewrite this line and put it in slope-intercept form.

Therefore, when . With this in mind, our y-intercept is 

Learning Tools by Varsity Tutors