We can put the two equations together with substitution, and we get
3x + 2y = 30
Now we have a single equation in two variables, so we don't have enough information to solve for both x and y.
The answer is 5.2 because if you do 12.60 - 10 it’s 2.6 so you add another 2.6 because it’s 2.6 for a half a pound so if you add the two half of pounds it will add up to one pound so it will be 2.6 + 2.6= 5.2 so basically 5.20$
Im not sure ask ur teacher
Sin (a+b) = sin a. cos b + cos a. sin b
a= 50° and b=40°, then
sin(50+40) = sin 50° . cos 40° + cos 50° . sin 40°
sin(50+40) = sin 90° = 1 and
sin 50° . cos 40° + cos 50° . sin 40° = 1
