ElectricPavlov

Extend line from O to N  angle BON = AOT = 60 

APT is in a triangle witht wo other angles 90 and 60 degrees

APT = 180 - 60- 90  = ......

common differece, d = 8         a1 = 11        a20 = -11 + 8(19) = 141

Sum = n/2 (a₁ + a₂₀)

        = 20/2 (-11 + 141) = ..........

(x-2)(x-1) <0        ONE of these must be less than zero   if EITHER is = 0   or if both are negative then the equation is not true

(x-2) < 0      (x-1)<0

x <2               x < 1              so between 1 and 2  (non-inclusive)   this is true    :    (1,2)      

A and B are complementary      they sum to 90^o

^{3x+2       +      8x   = 90     solve for  'x'       then angle B =   8x}

Angle B  and  C are supplementary ....they add to 180^o

    ^{then angle   C     =   180 - angle B       (you found angle B above)}

Angle B and C add to form a straight line (180^o)      .....and note that angle C = angle A

3x-2      +      12x+2       =    180^o

Now you can solve for 'x'    then angle C = 12x+2    ....and this equals  angle A

pi/3 = 1.047       roof function means = 2

sqrt45 = 6.7       floor function means = 6

8^2/3 = 4              floor functionmeans  = 4           2+ 6 + 4 = 12     (????    )

sum/n = 80

80n = sum

(80n-100)/(n-1) = 78

80n-100 = 78n -78

-22 = -2n

n = 11

d = dave original #  =   1.3 j

dave gives away 15%   leaving 85% of 1.3j   =   (.85)(1.3)(j)

j gives away 60% leaving 40%     .4 j  left

(.85)(1.3)(j) = 282 + .4j 

1.105 j  = 282 + .4j

.705j = 282

j = 400 originally        then dave had   1.3 (400) = 520

See your original post for edited answer,,,,,,

When x = 3      3x^2+2 = 29

ax-1 = 29    when x = 3

a(3) = 30

a = 10