285
x 71 equals 20235. hope that helps
<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>
Answer:
x= 5
Step-by-step explanation:
both lines are the same length
5x-6=2x+9
-2x -2x
3x-6= +9
+6 +6
3x = 15
÷3 ÷3
x= 5
Answer:
16.2
Step-by-step explanation:
The angle internal to the triangle at B is the supplement of the one shown, so is 65°. That is equal to the angle internal to the triangle at D. Since the vertical angles at C are congruent, the two triangles are similar by the AA theorem.
Corresponding sides of similar triangles are proportional, so we can write the proportion shown in the attachment:
BC/FC = DC/AC
BC = FC(DC/AC) = 21.6(7.2/9.6)
BC = 16.2 . . . . matches the first choice