Answer:
x = 10
Step-by-step explanation:
An euclidean triangle is defined to have sum of all 3 interior angles equal to 180°.
In the given triangle, we know three measurement:
You may be wondering, where does 90° come from. The answer is you can find it by looking if a triangle has a little square symbol or not. If it does, the measurement will always be 90°.
Now since we know that sum of 3 interior angles must equal to 180° in euclidean triangle. Therefore, sum up three of measurement then set to 180°.
[tex]\displaystyle{90 + 4x+10 + 40= 180}[/tex]
Evaluate and solve for the x-variable:
[tex]\displaystyle{90 + 4x+10 + 40= 180}\\\\\displaystyle{4x+140 = 180}\\\\\displaystyle{4x=180-140}\\\\\displaystyle{4x=40}\\\\\displaystyle{x=10}[/tex]
Therefore, the value of x is 10
