20 Answer: a₁ = 4
<u>Step-by-step explanation:</u>

21 Answer: n = 13
<u>Step-by-step explanation:</u>

22 Answer: n = 5
<u>Step-by-step explanation:</u>

Answer: y = 90°
Step-by-step explanation:
55.30786941 = sin-1 (148/180) round to 55.3° angle x
34.69213059 = cos-1 (148/180) . round to 34.7° "angle z" at right
34.7 +55.3 = 90
Sum of All angles of the triangle = 180° 180 -90 = 90
If angle x is 55.7 and angle z is 34.7° Angle y must be 90°
Ratio of inscribed arcs = ratio of chord to diameter
7 times 4 =28 this is cuz there is seven days in a week and 7x4
Answer:
See below.
Step-by-step explanation:
There is an infinite n umber of systems of equations that has (1, 4) as its solution. Are you given choices? Try x = 1 and y = 4 in each equation of the choices. The set of two equations that are true when those values of x and y are used is the answer.