Answer:
45°
Step-by-step explanation:
All angles in a triangle add up to 180°
180 - (90 + 45)
= 180 - 135
= 45
Therefore the missing angle is 45°
A) Find the Sum of the X values: 4 +5+8+9+13 = 39
B) Find the Sum of the Y values: 23 +12 +10 +9 +2 = 56
C) Find the Sum of x^2: 4^2 + 5^2 + 8^2 + 9^2 +13^2 = 355
D) The sum of the Y^2's: 23^2 + 12^2 + 10^2 + 9^2 + 2^2 = 858
E) Sum of x *y's: 4*23 + 5*12 + 8*10 + 9*9 + 13*2 = 339
N = number of sets = 5
Numerator of r = (E - A*B/N) = 339-39*56/5 = 339 - 436.8 = -97.8
Denominator of r = SQRT(C-A^2/N) x SQRT(D-B^2/N) =
SQRT(355-39^2/5) x SQRT(858-56^2/5) =
SQRT(50.8) x SQRT(230.8) =
7.1274 x 15.1921 =
108.2803
r = -97.8 / 108.2803
r = -0.903
Answer is A
