This table gives a few [tex]$(x, y)$[/tex] pairs of a line in the coordinate plane.

[tex]\[
\begin{array}{cc}
x & y \\
\hline
-38 & 40 \\
-23 & 30 \\
-8 & 20 \\
\end{array}
\][/tex]

What is the [tex]$x$[/tex]-intercept of the line?
[tex]\[\boxed{\ }\][/tex]



Answer :

To find the [tex]\(x\)[/tex]-intercept of the line given by the points [tex]\((-38, 40)\)[/tex], [tex]\((-23, 30)\)[/tex], and [tex]\((-8, 20)\)[/tex], we need to derive the equation of the line and then determine where it intercepts the [tex]\(x\)[/tex]-axis.

First, let's identify the slope [tex]\(m\)[/tex] of the line using any two of the given points. We'll use [tex]\((-38, 40)\)[/tex] and [tex]\((-23, 30)\)[/tex].

The formula for the slope [tex]\(m\)[/tex] is:
[tex]\[ m = \frac{y_2 - y_1}{x_2 - x_1} \][/tex]

Substitute the coordinates of the points:
[tex]\[ m = \frac{30 - 40}{-23 - (-38)} = \frac{-10}{15} = -\frac{2}{3} \][/tex]

Next, we use the slope [tex]\(m = -\frac{2}{3}\)[/tex] and one point to find the [tex]\(y\)[/tex]-intercept [tex]\(b\)[/tex]. Let's use the point [tex]\((-38, 40)\)[/tex].

The general equation for a line is:
[tex]\[ y = mx + b \][/tex]

Substituting [tex]\(m\)[/tex], [tex]\(x_1\)[/tex], and [tex]\(y_1\)[/tex]:
[tex]\[ 40 = -\frac{2}{3}(-38) + b \][/tex]

Solve for [tex]\(b\)[/tex]:
[tex]\[ 40 = \frac{76}{3} + b \][/tex]
[tex]\[ 40 = \frac{76}{3} + b \][/tex]
[tex]\[ 40 = \frac{76}{3} + b \][/tex]
[tex]\[ b = 40 - \frac{76}{3} \][/tex]
[tex]\[ b = 40 - 25.\overline{3} \][/tex]
[tex]\[ b = 14.\overline{6} \][/tex]

Now, we have the equation of the line:
[tex]\[ y = -\frac{2}{3}x + 14.\overline{6} \][/tex]

To find the [tex]\(x\)[/tex]-intercept, we set [tex]\(y = 0\)[/tex]:
[tex]\[ 0 = -\frac{2}{3}x + 14.\overline{6} \][/tex]

Solving for [tex]\(x\)[/tex]:
[tex]\[ \frac{2}{3}x = 14.\overline{6} \][/tex]
[tex]\[ x = 14.\overline{6} \cdot \frac{3}{2} \][/tex]
[tex]\[ x = 22 \][/tex]

So, the [tex]\(x\)[/tex]-intercept of the line is [tex]\(22\)[/tex].

[tex]\[ \boxed{22} \][/tex]