Question

3. If the two angles of a triangle are 45° and 55º find the third angle. What type of triangle is it?
4. If the vertex angle of an isosceles triangle is 90°, then find the base angles.​

Answer 1

3) Third angel = 180°- sum of two angle

=180°- (45°+55°)

= 189°-100°

=80°

Third angel is 80°

4) Sum of two equal angles = 180-90

= 90

As the two angles are same so the base angle = 90/2 = 45

Answer 2

Step-by-step explanation:

$\huge\fcolorbox{red}{yello}{Question}$

if the two angles of a triangle are 45° and 55° Find the third angle ? What type of triangle it is ?

$\huge\fcolorbox{blue}{green}{Given}$

• ANGLE A = 45°

• ANGLE B = 55°

• ANGLE C = ?

Angle A + Angle B + Angle C = 180° [ Angle Sum property ]

$\huge\fcolorbox{blue}{green}{Solution}$

• 45° + 55° + x = 180°

• 100° + x = 180

• x = 180° - 100°

• x = 80°

Hence,

• Angle A = 45°

• Angle B = 55°

• Angle C = 100°

Therefore , It is an Scalene Triangle....

$\huge\fcolorbox{red}{yello}{Question}$

If the vertex angle of an isosceles triangle is 90 ° then find the base angle?

$\huge\fcolorbox{blue}{green}{Given}$

• Vertex Angle of an isoceles triangle is 90°

As we know that two angles of an isosceles triangle are equal.

$\huge\fcolorbox{blue}{green}{Solution}$

• Let the base angles be x and x

• x + x + 90° = 180° [ Angle Sum property ]

• 2x + 90° = 180°

• 2x = 180° - 90°

• 2x = 90°

• x = 45°

Hence the base angle is 45°