Here, as I can see, you are adding fractions, and making sure you have a common denominator.
12) is correct
13) is correct
You got a common denominator, and added them up! Great job! <span />
I'll explain it simply for you
1st question
Of course you know phythagoras theorm
You even wrote it up there
It states that the sum of the square of the two sides of an equilateral triangle is equal to the square of the hypotenuse

Where C is the hypotenuse
*NOTE* :
HYPOTENUSE is the greatest side in a triangle!!
And that's where your mistake is!
So you should take the greatest side as C
So in Q3. 7, 24 and 26 are the given numbers
You'll make the smaller two numbers a and b and the greatest number C
Using the Formula you'll solve the left side first which is

Then the right side which is

And if both are equal then it is a right triangle otherwise it isn't!
Let
a=7
b=24
c=26
a^2 + b^2
7^2 + 24^2
49 + 576 = 625
GREAT, Now the right side
26^2 = 676
Since they aren't equal it isn't a right angled triangle...
Then let
a=7.5
b=10
c=12.5
7.5^2 + 10^2
= 56.25 + 100
= 156.25
12.5^2 = 156.25
They are EQUAL
Therefore it is a right triangle too
Hopefully I helped
Answer:
The answer is B I am on the time for learning format so It may differ but for me it's B
Step-by-step explanation:
Answer:
22
Step-by-step explanation:
ST is y and SU is 2y-4.
Note that SU = ST + TU = y + 18
So we have 2y - 4 = y + 18
2y - 4 = y + 18
2y = y + 22
y = 22
So ST is 22.
:)