Question 137144
BH/2=AREA
(H-7)H/2=39
(H^2-7H)/2=39
H^2-7H=78
H^2-7H-78=0
(H-13)(H+6)=0
H-13=0
H=13 ANSWER.
B=13-7=6 ANSWER.
PROOF:
13*6/2=38
78/2=38
38=38