<span>Replace tan θ with sin θ/cos θ
= sin²θ/cos θ + cos θ
Now multiply the right-hand side by cos θ/cos θ to get the same denominator:
= sin²θ/cos θ + cos²θ/cos θ
= (sin²θ + cos²θ)/cos θ
The numerator is equivalent to 1:
= 1 / cos θ
= sec θ</span>
I only know 1 & 4 .. 2 & 3 seem hard to me ..
X >7
X< -7
-
Since complementary angles add to 90°, (4x - 1) and (5x + 19), also add to 90°.
Thus, lets form an equation:
90 = 5x + 19 + 4x - 1
72 = 9x
x = 9
Thus, the measure of angle B is 64°.
For Question 1:
angle CAB, angle ABC, angle BCA
Question 2: angle BCD
