the diagram shows a triangle. what is the value of z? z = °

Answer:

$11$

Explanation:

Step1: Recall angle - sum property

The sum of interior angles of a triangle is $180^{\circ}$. So, $30^{\circ}+40^{\circ}+10z = 180^{\circ}$.

Step2: Simplify the left - hand side

$70^{\circ}+10z=180^{\circ}$.

Step3: Isolate the variable term

Subtract $70^{\circ}$ from both sides: $10z=180^{\circ}- 70^{\circ}$. $10z = 110^{\circ}$.

Step4: Solve for $z$

Divide both sides by $10$: $z=\frac{110^{\circ}}{10}=11^{\circ}$.