What are the values of a and b number 8

Step-by-step explanation:

(LOOK AT THE PICTURE)

ΔABC, ΔDBA and ΔDAC are similar (AAA). Therefore the corresponding sides are in proportion:

We have AB = b, AD = 20, AC = 29 and DC = 21. Substitute:

            cross multiply

          divide both sides by 21

and in proportion:

We have BD = a, AD = 20 and DC = 21. Substitute:

          cross multiply

  divide both sides by 21

-10i^2-4i

step-by-step explanation:

evaluate for p=2,q=5i

(2−4)(2+5i)i

(2−4)(2+5i)i

=−10i2−4i