Question

1) what is the value of x ?

Answer 1

Solution (1) :

Measure of angle ABC = (3x)°

Measure of angle CBD = (15x+18)°

Since angle ABC and angle CBD are a linear pair their sum will be equal to 180°¿

Which means :

$=\tt 3x + 15x + 18 = 180$

$=\tt 18x + 18 = 180$

$= \tt18x = 162$

$=\tt x = \frac{162}{18}$

$\color{plum} \tt= x = 9$

Thus, the value of x = 9.

Solution (2) :

From that equation, we know that the value of x = 9.

Which means :

Measure of angle ABC :

$=\tt 3x$

$=\tt 3 \times 9$

$\tt\color{plum} \: angle \: ABC = \tt27°$

Measure of angle ABC = 27°

Therefore, the measure of angle ABC = 27°

Solution (3) :

We know that x = 9

Which means :

Measure of angle CBD :

$=\tt 15x + 18$

$= \tt15 \times 9 + 18$

$= \tt135 + 18$

$\color{plum} \tt \: angle \: CBD = 153°$

Thus, angle CBD = 153°

Since the measure of angle ABC and angle CBD equals 180°[27+153=180°], we can conclude that we have found out the correct value of each angle.

Therefore, the measure of angle CBD = 153°