Answer: The value of X is 4 *cough*Bfb reference*cough*
We know that
Applying the law of cosines
c²=a²+b²-2*a*b*cos
C------> cos C=[a²+b²-c²]/[2*a*b]
in this problem
a=7.6 in
b=8.6 in
c=7.4 in
C=angle V
cos C=[7.6²+8.6²-7.4²]/[2*7.6*8.6]----> 0.5887
C=arc cos (0.5887)--------> C=53.93°-------> C=53.9°
the answer is
angle V is 53.9°
.75 Rounded to the nearest thousandth would be 0.750
Well, 15% of 60 is 9 so now you have to create a model :)