Question

Please help me thank you very much

Answer 1

Question 1:

Let's use the Pythagorean theorem.
$a=12$
$b=15$
$c=20$

If $c^2\ \textless \ a^2+b^2$, then the angle is acute.
If $c^2\ \textgreater \ a^2+b^2$, then the angle is obtuse.
If $c^2=a^2+b^2$, then the angle is right.

$c^2=400$
$a^2+b^2=144+225=369$

$\boxed{c^2\ \textgreater \ a^2+b^2}$

Thus, the angle is obtuse.

Question 2:

Use the Pythagorean theorem.
$a=b=8$
$c=?$
$a^2+b^2=c^2$

$8^2+8^2=c^2$
$c^2=64+64$
$c^2=128$

$c= \sqrt{128}$
$c= \sqrt{64*2}$
$\boxed{c=8 \sqrt{2} }$

That's your answer.
Hope this helps! :)

Answer 2

Here u go
1.B obtuse
2. C. 8/2