Question

Find the value of x.
x= 2
x= 13 2/3
x= 37
x= 39 1/2

Answer 1

x=37

Explanation:

Lets remember that in a triangle, the sum of all internal angles is equal to 180

this means the following

(x+13) + (2y) + (3y-20)=180

x+5y-7=180

Next, lets identify the supplementary angle, these meet the following condition. (3x+9)+2y =180

The system is given by these equations:

x+5y=187

3x+2y=171

if we isolate 'y' variable from second equation we have y= 1/2 * (171 - 3x), lets use that in the first.

x+5* 1/2 * (171 - 3x)=187

From this we obtain x=37