Question

if the three angle of a quadrilateral are 75° each then its fourth angle must be​

Answer 1

Given :

⬤ Three Angles of Quadrilateral are of 75° each .

To Find :

⬤ Fourth Angle of Quadrilateral .

Solution :

• First Angle = 75°
• Second Angle = 75°
• Third Angle = 75°

Let :

• Fourth Angle be x .

Now :

As we know that , Sum of all Angles of a Quadrilateral is 360 degree . Hence ,

$\sf{75^{\circ}+75^{\circ}+75^{\circ}+x=360^{\circ}}$

225 + x = 360°

x = 360 - 225

x = 135

Therefore , The Fourth Angle of Quadrilateral is 135 degree .

Check :

75° + 75° + 75° + x = 360°

75° + 75° + 75° + 135 = 360°

360° = 360°

Hence Checked

Answer 2

$\large \sf \green {\boxed {Sum\: of\:all\:angles\: of\:a \: quadrilateral \:is \:360°}}$

$\large \sf \blue{Let\: the \:4th \:angle\: be\: x}$

75° + 75° + 75° + x = 360°

225° + x = 360°

x = 360° - 225°

x = 135°

$\large \sf \green {\boxed {Fourth \:angle\: is\: 135°}}$