Y=5
Step By Step:
180-75-75
30
4y+10=30
4y=20
y=5
Since this is an isosceles, you know that angle B is congruent to angle C (they’re both 75°).
Answer:
16
Step-by-step explanation:

There are numerous ways to work a problem like this. One is shown above, where we multiply by the inverse of the denominator.
For this you can always use a calculator. Be sure to use parentheses around the denominator fraction.