First, find out x
x+15+2x+15=180
3x+30=180
3x=150
x=50
so the two angels are x+15=65(let's name is ∠5 for convenience), and ∠6= 2x+15=115
notice the two inner lines are marked as congruent, so
∠4=∠5=65
∠1=180-∠4-∠5=180-65-65=50
Name the right bottom angle ∠7, ∠3=∠7 and ∠3+∠7=the exterior angle 100 degree, therefore, ∠3=50
∠2+∠3=∠4, therefore, ∠2=∠4-∠3=65-50=15
∠1=50, ∠2=15, ∠3=50, ∠4=65
Answer:

⇒
[Factorized form]
Step-by-step explanation:
Given expression:

We need to make
the subject.
In order to do that we need to solve the expression for
in terms of
and 
We have,

Subtracting both sides by 


Taking square root both sides in order to remove square of 


The difference of squares can be factorized and written as:
[difference of squares
]
Answer:
triangles have a specific geometric shape.Because they have three sides, the pythagorean theorem for right angled triangle.
, (49)^1/2 we can write it as square root of 49 , and also the square root of 49 is 7