Question

Given ABC has interior angle measures with:

Answer 1

For this exercise it is important to remember the de sum of the interior angles of a triangle is 180 degrees.

For this case, you have the triangle ABC, and according to the information given in the exercise:

`\begin{gathered} \angle A=3x-15 \\ \angle B=x+5 \\ \angle C=x-10 \end{gathered}`

Knowing the above, you can set up the following equation:

`(3x-15)+(x+5)+(x-10)=180`

Now you must solve for "x":

`\begin{gathered} 3x-15+x+5+x-10=180 \\ 5x-20=180 \\ 5x=180+20 \\ 5x=200 \\ \\ x=(200)/(5) \\ \\ x=40 \end{gathered}`

Now, substitute the value of "x" into this equation:

`\angle A=3x-15`

Evaluating, you get that the measure of the angle A is:

`\angle A=3(40)-15=105\degree`

The answer is:

`\angle A=105\degree`