It’s the first one because the angles combined is a 90* angle and 30x2=60 with 30 and a + - 3 is 0
Answer:
To calculate the perimeter of a triangle, add the length of its sides. For example, if a triangle has sides a, b, and c, then the perimeter of that triangle will be P = a + b + c.

notice, the next term is obtained by subtracting 40 from the "current" one, meaning, is an arithmetic sequence, with a "common difference" of -40.
Answer:
20.3 cm. to the nearest tenth.
Step-by-step explanation:
Using the Pythagoras Theorem:
CR^2 = CS^2 + SR^2
= 6^2 + 13^2
= 205
CR = √205 cm.
UR = CR (because they are both radii of the circle).
So UR = √205
and SU =6 + √205
= 20.3 cm to the nearest tenth.