Question

7)
8)
find the slope of the line through each pair of points.

1. $(10, -18), (10, 6)$
2. $(8, 6), (11, -12)$
3. $(9, -9), (0, 6)$
4. $(-18, 8), (6, 11)$
5. $(-16, -1), (-20, -16)$
6. $(6, 11), (-12, -3)$
7. $(8, -13), (-3, -13)$
8. $(-18, 19), (1, 19)$

Explanation:

Step1: Recall slope formula

Slope $m = \frac{y_2 - y_1}{x_2 - x_1}$ for points $(x_1,y_1),(x_2,y_2)$
---

For 9) $(10, -18), (10, 6)$

Step2: Substitute into slope formula

$m = \frac{6 - (-18)}{10 - 10} = \frac{24}{0}$

Step3: Identify undefined slope

Division by 0 is undefined.

---

For 10) $(8, 6), (11, -12)$

Step2: Substitute into slope formula

$m = \frac{-12 - 6}{11 - 8} = \frac{-18}{3}$

Step3: Simplify the fraction

$m = -6$

---

For 11) $(9, -9), (0, 6)$

Step2: Substitute into slope formula

$m = \frac{6 - (-9)}{0 - 9} = \frac{15}{-9}$

Step3: Simplify the fraction

$m = -\frac{5}{3}$

---

For 12) $(-18, 8), (6, 11)$

Step2: Substitute into slope formula

$m = \frac{11 - 8}{6 - (-18)} = \frac{3}{24}$

Step3: Simplify the fraction

$m = \frac{1}{8}$

---

For 13) $(-16, -1), (-20, -16)$

Step2: Substitute into slope formula

$m = \frac{-16 - (-1)}{-20 - (-16)} = \frac{-15}{-4}$

Step3: Simplify the fraction

$m = \frac{15}{4}$

---

For 14) $(6, 11), (-12, -3)$

Step2: Substitute into slope formula

$m = \frac{-3 - 11}{-12 - 6} = \frac{-14}{-18}$

Step3: Simplify the fraction

$m = \frac{7}{9}$

---

For 15) $(8, -13), (-3, -13)$

Step2: Substitute into slope formula

$m = \frac{-13 - (-13)}{-3 - 8} = \frac{0}{-11}$

Step3: Simplify the expression

$m = 0$

---

For 16) $(-18, 19), (1, 19)$

Step2: Substitute into slope formula

$m = \frac{19 - 19}{1 - (-18)} = \frac{0}{19}$

Step3: Simplify the expression

$m = 0$

Answer:

1. Undefined
2. $-6$
3. $-\frac{5}{3}$
4. $\frac{1}{8}$
5. $\frac{15}{4}$
6. $\frac{7}{9}$
7. $0$
8. $0$