Question

from this adjoining figure show that ∠a=90°

Answer 1

Answer:

Step-by-step explanation:

Y+Y=90(co interior)

2Y=90

Y=45°

Similarly,X=45°

Now,sum of the angles of a∆ is 180

So,X+Y+A=180

45°+45°+A=180

A=189-90

A=90°

Hence proved

Hope you will get it

Answer 2

From the figure, we see that

⇒ $y + y=90^{o}$

⇒ $2y=90^{o}$

⇒ $y=45^{o}$

Therefore, $x=45^{o}$

As we know that, for aΔ sum of the angle is $180$,

⇒ $x +y+a=180$

Now, by plugging the values we get,

⇒ $45^{o} +45^{o} +a=180$

⇒ $a = 180-90$

⇒ $a=90^{o}$

Hence it is proved that, ∠a$=90^{o}$