Another important property of a line (or any curve on a coordinate plane) are its x- and y-intercepts: the points where the line intersects coordinate axes. Watch this lecture series and complete the interactive exercises.
Intercepts from an equation - Questions
Answers
1.
The \(y\)-intercept is the point where the graph intersects the \(y\)-axis. Since the \(y\)-axis is also the line \(x = 0\), the \(x\)-value of this point will always be \(0\).
The \(x\)-intercept is the point where the graph intersects the \(x\)-axis. Since the \(x\)-axis is also the line \(y = 0\), the \(y\)-value of this point will always be \(0\).
To find the \(y\)-intercept, let's substitute \(x = 0\) into the equation and solve for \(y\):
\(\begin{aligned}
4 \cdot 0-3 y &=17 \\
-3 y &=17 \\
y &=-\frac{17}{3}
\end{aligned}\)
So the \(y\)-intercept is \(\left(0,-\frac{17}{3}\right)\).
To find the \(x\) intercept, let's substitute \(y = 0 \) into the equation and solve for \(x\):
\(\begin{array}{r}
4 x-3 \cdot 0=17 \\
4 x=17 \\
x=\frac{17}{4}
\end{array}\)
So the \(x\)-intercept is \(\left(\frac{17}{4}, 0\right)\).
In conclusion,
- The \(y\)-intercept is \(\left(0,-\frac{17}{3}\right)\).
- The \(x\)-intercept is \(\left(\frac{17}{4}, 0\right)\).
2.
The \(y\)-intercept is the point where the graph intersects the \(y\)-axis. Since the \(y\)-axis is also the line \(x = 0\), the \(x\)-value of this point will always be \(0\).
The \(x\)-intercept is the point where the graph intersects the \(x\)-axis. Since the \(x\)-axis is also the line \(y = 0\), the \(y\)-value of this point will always be \(0\).
To find the \(y\)-intercept, let's substitute \(x = 0\) into the equation and solve for \(y\):
\(\begin{aligned}
y-3 &=5(0-2) \\
y-3 &=-10 \\
y &=-7
\end{aligned}\)
So the \(y\)-intercept is \( (0, -7)\).
To find the \(x\) intercept, let's substitute \(y = 0 \) into the equation and solve for \(x\):
\(\begin{aligned}
0-3 &=5(x-2) \\
-3 &=5 x-10 \\
7 &=5 x \\
1.4 &=x
\end{aligned}\)
So the \(x\)-intercept is \( (1.4, 0)\).
In conclusion,
- The \(y\)-intercept is \( (0, -7)\).
- The \(x\)-intercept is \( (1.4, 0)\).
3.
The \(x\)-intercept is the point where the graph intersects the \(x\)-axis. Since the \(x\)-axis is also the line \(y = 0\), the \(y\)-value of this point will always be \(0\).
The \(y\)-intercept is the point where the graph intersects the \(y\)-axis. Since the \(y\)-axis is also the line \(x = 0\), the \(x\)-value of this point will always be \(0\).
To find the \(x\) intercept, let's substitute \(y = 0 \) into the equation and solve for \(x\):
\(\begin{aligned}
0 &=11 x+6 \\
-6 &=11 x \\
-\frac{6}{11} &=x
\end{aligned}\)
So the \(x\)-intercept is \(\left(-\frac{6}{11}, 0\right)\).
To find the \(y\)-intercept, let's substitute \(x = 0\) into the equation and solve for \(y\):
\(\begin{aligned}
&y=11 \cdot 0+6 \\
&y=6
\end{aligned}\)
So the \(y\)-intercept is \( (0, 6) \). Generally, in linear equations of the form \(y=m x+b\) (which is called slope-intercept form), the \(y\)-intercept is \(( 0, b) \).
In conclusion,
- The \(x\)-intercept is \(\left(-\frac{6}{11}, 0\right)\).
- The \(y\)-intercept is \( (0, 6) \).
4.
The \(y\)-intercept is the point where the graph intersects the \(y\)-axis. Since the \(y\)-axis is also the line \(x = 0\), the \(x\)-value of this point will always be \(0\).
The \(x\)-intercept is the point where the graph intersects the \(x\)-axis. Since the \(x\)-axis is also the line \(y = 0\), the \(y\)-value of this point will always be \(0\).
To find the \(y\)-intercept, let's substitute \(x = 0\) into the equation and solve for \(y\):
\(\begin{aligned}
-7 \cdot 0-6 y &=-15 \\
-6 y &=-15 \\
y &=\frac{15}{6} \\
y &=\frac{5}{2}
\end{aligned}\)
So the \(y\)-intercept is \(\left(0, \frac{5}{2}\right)\).
To find the \(x\) intercept, let's substitute \(y = 0 \) into the equation and solve for \(x\):
\(\begin{aligned}
-7 x-6 \cdot 0 &=-15 \\
-7 x &=-15 \\
x &=\frac{15}{7}
\end{aligned}\)
So the \(x\)-intercept is \(\left(\frac{15}{7}, 0\right)\).
In conclusion,
- The \(y\)-intercept is \(\left(0, \frac{5}{2}\right)\).
- The \(x\)-intercept is \(\left(\frac{15}{7}, 0\right)\).