Answer:

Step-by-step explanation:
Pattern 1 consists of
small squares (here n = 1 and
).
Pattern 2 consists of
small squares (here n = 2 and
).
Pattern 3 consists of
small squares (here n = 3 and
).
Thus, pattern n consists of
small squares.
Answer:
x = 1
y = 30°
Step-by-step explanation:
is RS is ⊥ to TU then TS = US so we can use this equation to find 'x':
20x-3 = 5x+12
15x = 15
x = 1
we also know that RS intersecting with TU creates a 90° angle
if 3y = 90 then y = 30
Answer:
The value of cos Ф is ± 
Step-by-step explanation:
There are important rules for sin Ф and cos Ф
∵ sin Ф = 
∴ sin²Ф = 
∴ sin²Ф = 
→ By using the third rule above
∵ cos²Ф = 1 - sin²Ф
∴ cos²Ф = 1 - 
∴ cos²Ф = 
→ Take square root for both sides
∴ cos Ф = ± 
∴ The value of cos Ф is ± 