Question

three angles of triangle are x, x+3,x+9 find all three angles of triangle.​

Answer 1

The three angles of a triangle are x, x+3 and x+9.
According to Angle-Sum property of a triangle, the sum of all angles of a triangle = 180 degrees.

So,
180 = x + x + 3 + x + 9
180 = 3x + 3 + 9
180 = 3x + 12
180 - 12 = 3x
168 = 3x
168/3 = x
56 = x


Therefore,
x = 56,
3+x = 3 + 56 = 59
9 + x = 9 + 56 = 65

Answer 2

Given:

Angles of the triangle

• 1st angle = x
• 2nd angle = x + 3
• 3rd angle = x + 9

What to do?

Find the angles of the triangle.

How to do?

To find the angles of the triangle we have to know that sum of the interior angle of the triangle is 180°. Then we will form the equation using the angles given above.

Solution:

Sum of the interior angle of the triangle = 180°

⇒ x + (x + 3) + (x + 9) = 180°

After removing the brackets,

⇒ x + x + 3 + x + 9 = 180°

After rearranging the terms,

⇒ x + x + x + 3 + 9 = 180°

After solving the terms,

⇒ 3x + 12 = 180°

After moving 12 to RHS,

⇒ 3x = 180 - 12

After subtracting 12 from 180,

⇒ 3x = 168

After moving 3 to RHS,

⇒ x = $\frac{168}{3}$

After dividing 168 by 3,

⇒ x = 56°

Then substitute the values,

1st angle = x = 56°

2nd angle = x + 3 = 56 + 3 = 59°

3rd angle = x + 9 = 56 + 9 = 65°

∵ Hence, the angles of the triangle are 56°, 59°, 65° respectively.