Answer:

Step-by-step explanation:
1) Rewrite
in the form
, where a = y and b = 1.

2) Use Square of Difference:
.

3) Factor
.
1 - Ask: Which two numbers add up to 6 and multiply to -7?
-1 and 7
2 - Rewrite the expression using the above.

Outcome/Result: 
4) Rewrite the expression with a common denominator.

5) Expand.

6) Collect like terms.

7) Simplify
to 

Answer:
The approximated length of EF is 2.2 units ⇒ A
Step-by-step explanation:
<em>The tangent ratio in the right triangle is the ratio between the opposite side to the adjacent side of one of the acute angle in the triangle</em>
In the given figure
∵ The triangle DFE has a right angle F
∵ The opposite side to angle D is EF
∵ The adjacent side to angle D is DF
→ By using the tangent ratio above
∴ tan(∠D) = 
∵ DF = 6 units
∵ m∠D = 20°
→ Substitute then in the ratio above
∴ tan(20°) = 
→ Multiply both sides by 6
∴ 6 tan(20°) = EF
∴ 2.183821406 = EF
→ Approximate it to the nearest tenth
∴ 2.2 = EF
∴ The approximated length of EF is 2.2 units
Answer:
-9
Step-by-step explanation:
= 
Answer:

Step-by-step explanation:
remember: tan(theta) = opposite/adjacent