Answer:
Step-by-step explanation:
Expressions have no equal sign and a Equation has a result.
Here we have an arithmetic sequence:
a 1 = 20, d = 2, n = 35
S n = n/2 * ( a 1 + a n )
a 35 = a 1 + 34 d = 20 + 34 * 2 = 20 + 68 = 88
S 35 = 35/2 * ( 20 + 88 ) = 35 / 2 * 108 = 1,890
Answer: In total, the theater seats 1,890 people
Hi! I provided an image that I hope helps!
Answer:
Step-by-step explanation:
B + 87 +78 +66 = 360
B = 129 °
the angle next to B then is
180 = 129 + b '
51 ° = b '
A + 61 + b ' = 180
A = 68 °
