Connect with knowledgeable experts and enthusiasts on IDNLearn.com. Ask anything and receive thorough, reliable answers from our community of experienced professionals.

The table of values gives two points that lie on a line. Use the points to find the slope and [tex]\( y \)[/tex]-intercept of the line. Then use these values to write an equation of the line in slope-intercept form.

[tex]\[
\begin{array}{c|c}
x & y \\
\hline
4 & 1 \\
0 & 8 \\
\end{array}
\][/tex]

A. [tex]\( y = \frac{3}{8} x + 8 \)[/tex]

B. [tex]\( y = -\frac{3}{8} x + 8 \)[/tex]

C. [tex]\( y = \frac{7}{4} x + 8 \)[/tex]

D. [tex]\( y = -\frac{7}{4} x + 8 \)[/tex]


Sagot :

Sure, let's find the slope and y-intercept for the line passing through the points provided in the table.

The points given are:
- [tex]\( (4, 1) \)[/tex]
- [tex]\( (0, 8) \)[/tex]

### Step-by-Step Solution:

1. Finding the Slope ([tex]\( m \)[/tex]):
The formula for the slope [tex]\( m \)[/tex] between two points [tex]\( (x_1, y_1) \)[/tex] and [tex]\( (x_2, y_2) \)[/tex] is given by:
[tex]\[ m = \frac{y_2 - y_1}{x_2 - x_1} \][/tex]

Using our points [tex]\( (4, 1) \)[/tex] and [tex]\( (0, 8) \)[/tex]:
[tex]\[ m = \frac{8 - 1}{0 - 4} = \frac{7}{-4} = -\frac{7}{4} \][/tex]

2. Finding the Y-Intercept ([tex]\( b \)[/tex]):
The slope-intercept form of a line is [tex]\( y = mx + b \)[/tex], where [tex]\( b \)[/tex] is the y-intercept. To find [tex]\( b \)[/tex], we can use one of the points and the slope we just calculated. Let's use the point [tex]\( (4, 1) \)[/tex]:
[tex]\[ y = -\frac{7}{4}x + b \][/tex]
Substitute [tex]\( x = 4 \)[/tex] and [tex]\( y = 1 \)[/tex]:
[tex]\[ 1 = -\frac{7}{4}(4) + b \][/tex]
[tex]\[ 1 = -7 + b \][/tex]
Now solve for [tex]\( b \)[/tex]:
[tex]\[ b = 1 + 7 = 8 \][/tex]

3. Writing the Equation:
Now that we have both the slope and the y-intercept, we can write the equation of the line in slope-intercept form:
[tex]\[ y = -\frac{7}{4}x + 8 \][/tex]

Out of the given options, the correct equation of the line is:
[tex]\[ y = -\frac{7}{4} x + 8 \][/tex]