All SAT Math Resources
Example Questions
Example Question #11 : How To Find X Or Y Intercept
What are the -intercept(s) of the following line:
We can factor and set equal to zero to determine the -intercepts.
satisfies this equation.
Therefore our -intercepts are and .
Example Question #11 : How To Find X Or Y Intercept
Which of the following lines does not intersect the line ?
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 #12 : How To Find X Or Y Intercept
Find the y-intercept of .
3
7
5
12
14
7
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 #173 : Geometry
The slope of a line is . The line passes through . What is the x-intercept?
None of the available answers
The equation for a line is:
, or in this case
We can solve for by plugging in the values given
Our line is now
Our x-intercept occurs when , so plugging in and solving for :
Example Question #15 : How To Find X Or Y Intercept
Determine the x-intercept for the equation:
The x-intercept is the x-value when the value of . Substitute this value and solve for .
The x-intercept is .
Example Question #14 : How To Find X Or Y Intercept
What is the y intercept of
y=-3
y=3
y=12
The line does not cross the y axis.
y=3
To find the y intercept, substitute x=0
Example Question #15 : How To Find X Or Y Intercept
At what point does the line intersect the y-axis?
None of the given answers
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 .
Example Question #16 : How To Find X Or Y Intercept
Give the area of the triangle on the coordinate plane that is bounded by the -axis, and the lines of the equations and .
None of the other choices gives the correct response.
It is necessary to find the vertices of the triangle, which can be done by finding the three points at which two of the three lines intersect.
The intersection of the -axis - the line - and the line of the equation , is found by noting that if , then, by substitution, ; this point of intersection is at , the origin.
The intersection of the -axis and the line of the equation is the -intercept of the latter line. Since its equation is written in slope-intercept form , with the -coordinate of the -intercept, this intercept is .
The intersection of the lines with equations and can be found using the substitution method, setting in the latter equation and solving for :
Since , , making the point of intersection.
The lines in question are graphed below, and the triangle they bound is shaded:
If we take the vertical side as the base, its length is seen to be 3; the height is the horizontal distance to the opposite vertex, which is its -coordinate . The area is half the product of the two, or
.
Example Question #26 : X And Y Intercept
Give the area of the triangle on the coordinate plane that is bounded by the lines of the equations , and .
It is necessary to find the coordinates of the vertices of the triangle, each of which is the intersection of two of the three lines.
The intersection of the lines of the equations and can easily be found by noting that since , by substitution, , making the point of intersection .
The intersection of the lines of the equations and can be found by substituting for in the latter equation and evaluating :
The point of intersection is .
The intersection of the lines of the equations and can be found by substituting for in the latter equation and solving for :
, so , and this point of intersection is .
The lines in question are graphed below, and the triangle they bound is shaded:
We can take the vertical side as the base of the triangle; its length is the difference of the -coordinates:
The height is the horizontal distance from this side to the opposite side, which is the difference of the -coordinates:
The area is half their product:
Example Question #21 : How To Find X Or Y Intercept
Give the area of the triangle on the coordinate plane that is bounded by the axes and the line of the equation .
It is necessary to find the vertices of the triangle, each of which is a point at which two of the three lines intersect.
The two axes intersect at the origin, making this one vertex.
The other two points of intersection are the intercepts of the line of equation . Since this equation is in slope-intercept form , where is the -coordinate of the -intercept, then , and the -intercept is the point . The -coordinate of the -intercept, , can be found by setting and solving for :
.
The three vertices are located at
The line in question is shown below, with the bounded triangle shaded in:
The lengths of its legs are equal to the absolute values of the nonzero coordinates of its two intercepts - . The area of this right triangle is half their product:
.