₦airaland Forum

NDSMELODY:
Nothing is wrong with d question..any one with explanatory solution shld post it...poster of d questn shld pls correct d work if there is any error but if otherwise 75 degree is d ans then

kabvic:
40°

Corresponding angles

Neoguru6:
x= 40° (Corredponding angles)

naaija:
Yes I did.

How do I contact you ?

Darivie04:
Does the hole go on to pass through the wider cylinder?

Bolognese:
I think this is a more realistic diagram to your question.

The stuff is in 3D.

naaija:
Uncle - I

Roon9:
This is the diagram . nothing to it jor

Abeos:
Yeah the diagram is wrong. I later saw question required calculation of the bearing and that be solved using a 2d diagram

moniniola:
ok when I have them,I will contact you

naturalwaves:
Lolz.
They are much o. I do not know the names you have on your list already. Perhaps I could add more.

naturalwaves:
I bet you did not realise that there are a lot of badazz mathematicians on Nairaland.

moniniola:
Jeez! do questions like this still exist?somebody like me will drive my children early to school so they can copy maths assignment lol...I hate that subject

naturalwaves:
Okay. Abeos made a mistake in his labelling though.

naturalwaves:
I see! Doing 3D imaging and teaching the concept is a bit advanced for that level considering the fact that 95%+ of secondary schools do not have the resources to teach such. It cannot be well illustrated on a white board for students. I may teach in a privileged school with all the necessary facilities like Interactive Flat Panels and necessary software to make an illustration. However, less than 5% of schools have this.
If I get you right, do you mean to say that I gave the correct 2D analysis and imaging while you guys gave the 3D solution?

naturalwaves:
I see! Doing 3D imaging and teaching the concept is a bit advanced for that level considering the fact that 95%+ of secondary schools do not have the resources to teach such. It cannot be well illustrated on a white board for students. I may teach in a privileged school with all the necessary facilities like Interactive Flat Panels and necessary software to make an illustration. However, less than 5% of schools have this.
If I get you right, do you mean to say that I gave the correct 2D analysis and imaging while you guys gave the 3D solution?

Rezos017:
Most bright students, even a huge percent of maths teachers, would still struggle to come up with a diagram that captures this question. Its not the solution that's difficult; its the diagram. Most times, students are taught only two dimensional bearing problems, but three dimensional problems like the one in the post are completely ignored.

naturalwaves:
Were the students expected to draw a 3D diagram for the straightforward sketch? Let me see the diagram you have.

Rezos017:
Notice the correction: the angle of elevation of the top of the tower B from point D (not point C in the previous diagrams) is 35 degrees

Rezos017:
Just a little rotation.

naturalwaves:
SOLUTION

Question says;
C and D are observational posts on the same horizontal ground at the foot A of a vertical tower AB. The tower is 18m due North of D and 24m due East of C

Question should be
C and D are observational posts on the same horizontal ground AS the foot A of a vertical tower AB. The tower is 18m due North of D and 24m due East of C
After correcting the grammar, this is how it should be solved.

STEP 1

Mark a dotted point as the point D and trace it up to another dotted point. The second dotted point represents the tower. This should be a straight line. why? Because the question says the tower is 18m due North of D. So, label the line as 18m


STEP 2

From that second dotted point which represents the tower, draw another straight, dotted lines to the left and put a dot at the end to represent C. Label it as 24m. Why? The question says that, the tower is 24m due East of C


STEP 3
From the question , we know that points C and D are on the same horizontal ground. So, draw a straight line to join points C and D


STEP 4
Draw a straight line to join the line /CD/ from our initially dotted point that represents the tower. THAT STRAIGHT LINE YOU HAVE JUST DRAWN IS THE TOWER AB


STEP 5

We know from the question that the foot of the tower is A and the top is B. So, label the bottom that is now on the same line as /CD/ as A and label the top as B. You will then observe that the diagram is in line with the question as C,A and D are all on the same line.

I will attach the necessary pictures when I get on a phone I can snap with or when I can sketch. I am on the laptop now.
I hope this helps someone.

Note that in the diagram, a straight line was drawn fom D to the tower point to show that the tower point is due north. The line is not the tower

CC: Castro316, Rezos017, Mrshape,Abeos, Airtimex

Rezos017:
There you have it. Virtually every detail of the question is captured in the diagram. It makes comprehension and calculating much easier.