I just need help with solving this problem

Question

if tanA=4/3 and sinB=45/53 and angles A and B are in quadrant 1, find the value of tan(A+B)

Answer 1

tan(A+B) =( tanA + tanB) / (1 - tan A tanB)

sin B = 45/53 ---> opposite = 45 and hypotenuse = 53

pythagorean says adjacent = sqrt( 53^2 - 45^2) =28

so tan B = 45/28

Finally , tan(A+B) = (4/3 + 45/28) / (1 - (4/3)(45/28))

= (112 + 135)/84 divided by ( 1 - 180/84)

= (247)/84 divided by ( 84-180)/(84)

= 247/84 * 84/(-96)

= -247/96