Since the intersection is - by definition - common to both sets, we can work out the number of people that use only the fitness suite or the swimming pool.
We know that 57 people use the fitness suite, but 36 of those are already counted in the intersection. So, 57-36=21 people use only the fitness suite.
The same goes for the swimming pool: 49-36=13 people use only the swimming pool.
So, we have:
- 21 people using fitness suite only
- 13 people using swimmng pool only
- 36 people using both
This sums to 21+13+36=70 people. We deduce that 30 people don't use any of the features.
Try multiplaying all sides
3. is the answer, as you can see D is one and a half units to the right of the y axis at a height of 3 units and C is one and a half units to the left of the y axis with the same height. So D is "reflected" about the y axis and only the x coordinate changes sign from positive to negative.
This one is super difficult, I see your struggle but the answer is A.
given: s is the midpoint of rt
definition of midpoint: rs st
given: st xy
transitive property of congruence: rs xy