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[inkyy]

I HAVE A QUESTION!
TYPE OF QUESTION: Maths
YOUR QUESTION: So I sat my national 5 maths exam today and there was a question I had no clue how to do. The people i was chatting too after the exam didnt know either and its bugging me.
I've drawn it out from memory (lmao) so the number 2.6 may be incorrect (it was 2 point something) but I dont think that matters. This was the only info we were given - I thought it could be similar shapes/scale factor eg but you dont have a full side for x / x + 2.6. thank you so so much!!

[aequilibrium]

@inkyy - In this type of exercise you were probably meant to use the triangle similarity just like you said. You have the two vectors that correspond to the same side in both angles which is enough to know the similarity ratio, so all you need to do is find x with that ratio:


7 / 5 = (x + 2.6) / x
7x = 5 (x + 2.6)
7x = 5x + 13
7x - 5x = 13
2x = 13
x = 6.5

If I didn't commit any mistake and 2.6 is the correct number, then 6.5 might have been the answer.
I hope this helped! If you have any questions feel free to ask ^-^

[Burrito Bunny]

@inkyy

I did it out in an image, but it looks like someone else beat me to it. Here's the image if you still would like to see it written out in a slightly different way. c:

image

[inkyy]

@aequilibrium
@Burrito Bunny
thank you both so much!!! that makes lots of sense & im gutted cos i put down some of the right working and scored it out xD thanks again!

[Jaskiest]

I HAVE A QUESTION!
TYPE OF QUESTION: Maths
YOUR QUESTION: '(a + √b)² = 49 + 12√b
Given that a and b are integers, and b is a prime number, find a and b'
really confused on this from my maths homework - would appreciate any help!

edit - put the wrong thing in the brackets oops
I got as far as a² + 2√b + b = 49 + 12√b but wasn't sure how to continue it

[BuddyMaltese]

I HAVE A QUESTION!
TYPE OF QUESTION:
Pre-Calc
YOUR QUESTION:

thank you <3

Edit: is the true speed of the boat 22.8 and the speed of the water 7.5?

[Waki]

up

[aequilibrium]

@Lafayette - You have that step wrong, it should be:

a² + 2 a √b + b = 49 + 12 √b

But I'm not sure how to continue either. All I can think of right now is the quadratic formula but that would probably take too long to solve or maybe we can't even solve this with it xs

[ladybug astronaut]

I HAVE A QUESTION!
TYPE OF QUESTION: Maths
YOUR QUESTION: '(a + √b)² = 49 + 12√b
Given that a and b are integers, and b is a prime number, find a and b'
really confused on this from my maths homework - would appreciate any help!

edit - put the wrong thing in the brackets oops
I got as far as a² + 2√b + b = 49 + 12√b but wasn't sure how to continue it

Aight, now that u put that square root in there, I can help (:

So. First of all. Aequallibrium is right, that middle part is 2a(sqrt(b))

At that point, think of sqrt(b) as it's own variable.

The only thing that can make 12sqrt(b) is 2a(sqrt(b)) because nothing else has that variable

Divide both sides by sqrt(b) and you have 12=2a

That means a=6

Now does that work?

The other parts of the equation are 49= a^2 + b

a^2 is 36, if a is 6

49-36= 13 (:

b being 13, I'm pretty sure, satisfies the conditions, right?

Let me know if that all made sense or if I missed something obvious (:

[Kaidaft]

I HAVE A QUESTION!
TYPE OF QUESTION:Math
YOUR QUESTION: f(x)= 2x³ - 14x² + 24x
'Factor each trinomial and find the Zeros.'
(zeros are also known as roots or x-intercepts)