To solve problems like this, we must simply break it down and read each part carefully. We can also set it up as a math problem to make it easier to visualize.
The elevator starts on the twentieth floor, so we will represent that with 20.
20
It goes down 11 floors, so we can represent that with a -11.
20-11=9
Now we are on floor 9. Then, we go up 5 floors, so we can represent that with a 5.
9+5=14
Using the math above, we can see the elevator is on the 14th floor.
70 ft because 7 is bigger than 5 and 7x10=70
Answer:
The step 4 is not what he should have done. But the wrong is step 5, because if he added -2x both sides, it would give the following equation:

and not 
Note that in step 4 he should have added 2x and not -2x to both sides, but we still have the equality. The problem is that step 5 is totally wrong.
I don't know what answer is expected to this question, but I would mark step 5, because this is mathematically wrong.
Solving the equation

Using distribution

Add
both sides


Add 12 both sides

Divide both sides by 5

Answer:
19
Step-by-step explanation:
product is the answer of multiplying two numbers together
342/18=19
check
19x18=342
If < A and then m< A + m/B = 90°, then D. Definition of Complementary Angles
<h3>What is a complementary angle?</h3>
When the sum of two angles is 90°, the angles are said to be complementary. In other words, if two angles add up to form a right angle, they are called complementary angles. The two angles are said to complement each other in this context.
Supplementary angles are two angles that add up to 180 degrees, whereas complementary angles are two angles that add up to 90 degrees.
An angle measuring 72 degrees has a complement of 18 degrees.
Therefore, based on the information given, the correct option is D.
Learn more about complementary angles on:
brainly.com/question/16281260
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