91Ó°ÊÓ

If two angles are equal or congruent in a triangle then the sides opposite to those angles are equal.

Since $∠B=∠C=70°$hence both are equal angles.

Sincein a triangle having two equal angles, sides opposite to these angles are also equal.Hence both the sides are equal.

Therefore, the answer is.

The lines that lie on top of each other are coincident lines.

As from the figure, AX and XB are lie on the line AB. Therefore, both coincide on AB.

Since, AX and XB coincides on AB therefore $AB=AX+XB$

Thus, the answer is $=$.

If $a=b+c$ and $c>0$ then $a>b$.

As from the figure, AX and XB coincides on AB therefore $AB=AX+XB$.

If $a=b+c$ and $c>0$ then $a>b$. As $AB=AX+XB$so $AB>XB$.

Thus, the answer is $>$.

Since in a triangle having two equal angles, sides opposite to these angles are also equal. Hence $AB=AC$. Since $AB=AX+XB$ and $AB=AC$ therefore, $AC=AX+XB$

If $a=b+c$ and $c>0$ then $a>b$.

If $a=b+c$ and $c>0$ then $a>b$. As $AC=AX+XB$so $AC>XB$.

Thus, the answer is $>$.