I think it's the last one, i'm not sure though
See the attached figure to better understand the problem
we know that
1) First way to find the value of ain the triangle ABC
<span>applying the Pythagorean theorem
AC</span>²=AB²+BC²--------> BC²=AC²-AB²-----> BC²=25²-15²-----> BC²=625-225
BC²=400--------> BC=20 units
a=BC
a=20 units
2) Second way to find the value of a
in the triangle ABD
AB²=AD²+BD²--------> BD²=AB²-AD²-----> BD²=15²-9²---> BD²=144
BD=12 units
in the triangle BDC
a=BC
BC²=BD²+DC²-----> 12²+16²----> 144+256------> BC²=400
BC=20 units
a=20 units
It could be many things like 30 + 4 = 34
25.13cm^2 or 8pi. The radius of a circle is 2 x pi x r^2. R is the radius. 2 x pi x 2^2cm -> 2 x pi x 4cm -> 8cm x pi -> 25.13cm^2. Leaving the answer in terms of pi would be 8pi.
Answer:
7. x=19 2x=38
8.x=23 3x=69
9.x=12 (50-2)/4=12
10.x=15 (31-1)/2
11.x=16 (84-4)/5
12.x=27 (55-1)/2
Step-by-step explanation:
if 2 angles are opposite, it's the same